Tola vs. Gram vs. Troy Ounce: The Complete Investment Guide

The Global Tower of Babel: Why Gold Has So Many Measurements

If you have watched the financial news in New York, you have heard gold priced in "ounces." If you have purchased a gold necklace in Dubai, you were likely quoted a making charge in "grams." And if you have sat in a family jeweler's shop in Mumbai, Karachi, or Dhaka, the entire conversation was conducted in "tolas."

Why does gold—the most universal currency in human history—lack a universal language of measurement? The answer lies in thousands of years of separate regional mercantile traditions colliding with globalized commodity trading.

When investors, retail buyers, and jewelers cross borders, understanding the tola vs gram vs ounce differences is not just academic trivia; it is a financial necessity to prevent overpaying for precious metals. This comprehensive guide will dismantle the differences between these three titans of weight measurement, providing you with the exact formulas and context needed to evaluate any gold deal on the planet.

The Troy Ounce: The Monarch of the Global Spot Market

When you see a headline flashing across Bloomberg or CNBC that says, "Gold breaches $2,000," the invisible suffix at the end of that sentence is "...per troy ounce."

What is a Troy Ounce?

The Troy ounce (abbreviated as 'oz t' or simply 'oz' in precious metal contexts) is the only unit of measure used by the London Bullion Market Association (LBMA) and the COMEX futures exchange. It is the absolute baseline against which all global gold derivatives and spot prices are settled.

• Exact Gram Conversion: 1 Troy Ounce = 31.1034768 grams
• Exact Tola Conversion: 1 Troy Ounce = 2.6666... Tolas

The Avoirdupois Trap

A critical mistake many novice gold investors make is confusing the "troy ounce" with the standard "avoirdupois ounce" used to weigh groceries in the United States and the UK. An avoirdupois ounce is only 28.3495 grams. A troy ounce is noticeably heavier (31.103g). If you buy an "ounce" of gold from an unverified online seller and receive 28 grams instead of 31.1 grams, you have fallen victim to the avoirdupois trap.

Who uses the Troy Ounce? Central banks compiling gold reserves, institutional ETF managers, global bullion dealers, and western retail buyers purchasing standard 1 oz American Gold Eagles or Canadian Maple Leaf coins.

The Gram: The Modern Metric Universalist

Introduced formally during the French Revolution, the gram (g) is the base unit of mass in the metric system (SI). Over the last century, it has mercilessly conquered almost every other measurement system on the planet due to its elegant base-10 mathematics.

Why the Gram Dominates Retail Jewelry

Regardless of what region you are in, almost all modern jewelers use digital scales calibrated to measure in grams. It provides incredibly fine precision (down to the milligram) which is necessary when pricing out diamonds, alloys, and intricate filigree work on necklaces and bracelets.

In wholesale bullion, the gram is the foundation of the Kilobar (1,000 grams). The kilobar is the standard contract size for the Shanghai Gold Exchange (SGE) and is highly popular in Asian manufacturing and investment sectors.

• Ounce Conversion: 1 Gram = 0.0321507 Troy Ounces
• Tola Conversion: 1 Gram = 0.085735 Tolas

The Tola: The Unyielding Cultural Anchor of the East

Despite the dominance of the troy ounce in Wall Street and the gram in global science, the tola refuses to vanish. It remains the undisputed king of gold measurement across the Indian subcontinent (India, Pakistan, Bangladesh, Nepal) and by extension, the massive gold souks of the Persian Gulf (UAE, Bahrain, Qatar) which cater heavily to the South Asian diaspora.

Defining the Tola

As we covered extensively in our guide on The 10 Gram Tola Myth, the standardized definition of the tola was established during British rule in 1833. It was pegged to the weight of the Indian silver Rupee coin, which was minted to weigh exactly 180 troy grains.

• Exact Gram Conversion: 1 Tola = 11.6638038 grams
• Exact Ounce Conversion: 1 Tola = 0.375 Troy Ounces

The synergy between the tola and the troy ounce is fascinating and not accidental. Because the British standardized the tola based on troy grains (180 grains), the tola actually divides perfectly into troy ounces. Three-eighths (3/8) of a troy ounce is exactly one tola.

The Almighty 10-Tola Bar (TT Bar)

The true power of the tola in the modern wholesale market is embodied by the TT Bar. Weighing exactly 10 tolas (116.638 grams or 3.75 troy ounces), this palm-sized gold biscuit is the premier vehicle for physical gold hoarding and smuggling in the East. Their uniform size, ease of concealment, and lack of serial numbers (on older cast varieties) made them the currency of choice for the hawala system. Today, pristine minted TT bars from Swiss refiners like PAMP Suisse are highly sought after premiums over spot price in Dubai.

Comprehensive Conversion Matrix: Tola, Gram, and Troy Ounce

Before diving deeper into regional usage and investment strategies, it is essential to establish a complete cross-conversion matrix between all three units. These are the exact mathematical relationships that every gold buyer, jeweler, and investor should commit to memory. You can also verify these numbers instantly using our gram to tola converter tool.

From Tola to Gram and Ounce

From Troy Ounce to Gram and Tola

From Gram to Tola and Ounce

This comprehensive gram-to-tola reference is also available as a printable resource on our full conversion chart page.

When to Use Which Unit: Regional Market Context

Choosing the right unit of measurement is not a matter of personal preference. It is dictated by the market you are operating in, the type of transaction you are conducting, and the counterparty you are dealing with. Understanding regional conventions prevents confusion, miscommunication, and costly conversion errors.

Tola Markets: South Asia and the Gulf

The tola is the dominant unit of trade in India, Pakistan, Bangladesh, Nepal, and Sri Lanka. It is also the primary unit used in the gold souks of the United Arab Emirates, Bahrain, Qatar, Kuwait, and Oman, largely because of the massive South Asian expatriate communities driving demand in those Gulf economies.

In these markets, jewelers quote the daily gold price per tola prominently on LED boards. Bridal sets, bangles, chains, and investment bars are all weighed, priced, and sold in tolas. If you walk into Zaveri Bazaar in Mumbai or the Gold Souk in Deira and ask for a price in troy ounces, you will receive a blank stare.

Additionally, newspaper and television gold rate listings in countries like Pakistan, India, and Bangladesh publish daily rates exclusively in the local currency per tola. For a deeper exploration of how the tola varies across nations, see our guide on tola measurements in different countries.

Gram Markets: Europe, East Asia, and Institutional Trade

The gram is the universal language of precision jewelry manufacturing worldwide. Even in tola-dominated markets, the actual weighing scale on the jeweler's counter reads in grams. The gram is also the primary unit for:

• European retail bullion: Small investment bars (1g, 5g, 10g, 20g, 50g, 100g) sold by refiners like Valcambi, Heraeus, and Umicore
• Chinese gold market: The Shanghai Gold Exchange (SGE) quotes gold in Chinese Yuan per gram, and the standard contract is the kilogram bar (1,000 grams)
• Japanese gold market: Retail gold sold primarily in grams by dealers like Tanaka Kikinzoku
• India's MCX exchange: The Multi Commodity Exchange of India quotes gold futures in Indian Rupees per 10 grams

Troy Ounce Markets: Western Institutional and Commodity Trading

The troy ounce is the exclusive unit for global commodity exchanges and central bank reserves. COMEX (CME Group) in New York, the LBMA in London, and the global XAU/USD forex pair all use the troy ounce. Central banks report gold reserves in metric tonnes but price acquisition in troy ounces. Western retail coins (American Eagle, Canadian Maple Leaf, Austrian Philharmonic, South African Krugerrand) are all minted in 1 troy ounce denominations.

Historical Origins of Each Measurement System

Understanding the history behind these measurement systems reveals why each one persists so stubbornly in its own domain, even in an era of metrication.

The Ancient Roots of the Troy Ounce

The troy ounce traces its lineage to the medieval French trading city of Troyes, which hosted one of the great annual trade fairs of Europe in the 12th and 13th centuries. Merchants from across the continent gathered there to buy and sell precious metals, spices, and textiles. To standardize transactions, they adopted a weight system based on the Roman uncia (ounce), calibrated to exactly 480 grains.

The English Crown formally adopted the Troy system in 1527 under Henry VIII, making it the official standard for weighing gold and silver throughout the British Empire. When the London Gold Market was formalized in the 17th century, the troy ounce became its unquestioned foundation. That lineage has never been broken, which is why in 2026, every Bloomberg terminal on the planet still flashes gold prices in USD per troy ounce.

The Revolutionary Birth of the Gram

The gram was born from the radical rationalism of the French Revolution. In 1795, the new French Republic, eager to eradicate every remnant of the feudal ancien regime, decreed that the kilogram would replace all previous weight systems. One gram was defined as the mass of one cubic centimeter of water at its maximum density (approximately 4 degrees Celsius).

Napoleon's conquests spread the metric system across Europe, and by the 20th century, virtually every nation on earth had adopted it for science, trade, and daily commerce. Today, the gram is the global language of precision measurement, governed by the International Bureau of Weights and Measures (BIPM) in Paris.

The Imperial Heritage of the Tola

The tola predates British India, originating in the Vedic-era tolaka or tula, an ancient Sanskrit unit of mass. However, its modern standardized form was codified by the British East India Company in 1833, when they pegged the weight of the Indian Silver Rupee coin at exactly 180 troy grains (11.6638038 grams). The tola, being defined as the weight of one Rupee, inherited this exact value.

This deliberate alignment with the troy grain system was a stroke of colonial administrative genius. It allowed the British to seamlessly translate between their own troy-based monetary system and the Indian subcontinent's existing weight traditions. The legacy of that 1833 decision persists today across billions of gold transactions annually. To learn more about what exactly a tola is and how it was standardized, see our dedicated reference page.

Why International Markets Use Troy Ounce While South Asia Uses Tola

The persistence of these parallel systems is not irrational. It is the result of deeply embedded cultural, institutional, and commercial infrastructure that resists unification.

The Institutional Lock-In of the Troy Ounce

Global commodity exchanges, central bank accounting standards, mining company financial reports, and ETF prospectuses are all denominated in troy ounces. Changing this would require rewriting thousands of legal contracts, regulatory frameworks, and software systems across COMEX, LBMA, the World Gold Council, and dozens of national central banks. The switching cost is astronomical, so the troy ounce remains the incumbent standard for institutional gold.

The Cultural Lock-In of the Tola

In South Asia, gold is not merely a financial asset. It is a cultural institution woven into weddings, dowries, religious ceremonies, and generational wealth transfer. When a grandmother in Lahore tells her granddaughter that she is leaving her "15 tolas of gold," that phrase carries emotional and cultural weight that transcends metric conversion. The tola is the language of family gold, of auspicious weight targets for bridal jewelry, and of daily newspaper rate listings that have been published in tola for over a century.

Attempting to replace the tola with grams in a Pakistani newspaper's gold rate column would be as culturally jarring as replacing ounces with grams in an American cooking recipe. The diverse gold weight units used around the world reflect these deep cultural attachments.

Gold Trading: How Prices Are Quoted in Different Markets

One of the most practical applications of understanding these three units is navigating the wildly different price quoting conventions used by major gold exchanges and retail markets around the world.

COMEX (New York): USD per Troy Ounce

The COMEX division of CME Group is the world's largest gold futures market. The standard contract (GC) is for 100 troy ounces of gold, with prices quoted in US Dollars per single troy ounce. The "mini" contract (QO) covers 50 ounces, and the "micro" contract (MGC) covers 10 ounces. When you hear "gold hit $2,400 today," that is the COMEX front-month futures price per troy ounce.

LBMA (London): USD per Troy Ounce

The London Bullion Market Association publishes twice-daily gold "fixes" (now called the LBMA Gold Price) in USD per troy ounce. The standard "Good Delivery" bar traded on the LBMA weighs approximately 400 troy ounces (12.4 kilograms). This is the benchmark used by central banks and institutional gold buyers worldwide.

MCX (Mumbai): INR per 10 Grams

India's Multi Commodity Exchange quotes gold futures in Indian Rupees per 10 grams. The standard contract size is 1 kilogram (100 lots of 10 grams). This is the gateway where the global troy ounce price gets translated into the Indian domestic market. To convert an MCX price to a per-tola price, divide by 10 to get the single-gram rate, then multiply by 11.6638.

Local Retail Markets: Price per Tola or per Gram

In the gold souks of Dubai, Karachi, Mumbai, and Dhaka, the daily retail price is prominently displayed in the local currency per tola (and sometimes per gram alongside it). These local rates incorporate the global spot price plus import duties, dealer premiums, and local taxes. Our gold price per tola tracker helps you compare these local quoted rates against the true international benchmark.

Shanghai Gold Exchange (SGE): CNY per Gram

China, the world's largest gold consumer, prices gold on the SGE in Chinese Yuan per gram. The benchmark contract (Au99.99) trades in lots of 1,000 grams (1 kilogram). This gram-based pricing reflects China's full adoption of the metric system for precious metal commerce.

Practical Scenarios: Converting Jewelry Weights Between Systems

Theory is useful, but real-world scenarios are where conversion mastery saves you money. Here are practical examples you will encounter when buying, selling, or insuring gold jewelry across different markets.

Scenario 1: Buying a Bridal Necklace in Dubai, Comparing Prices Online

You are in a Dubai gold souk and a jeweler quotes you a 22K bridal necklace weighing 4.5 tolas. You want to verify the gold content against international rates.

1. Convert tolas to grams: 4.5 tolas x 11.6638 = 52.487 grams of 22K gold
2. Calculate pure gold content (22K = 91.6%): 52.487 x 0.916 = 48.078 grams of pure 24K gold
3. Convert to troy ounces: 48.078 / 31.1035 = 1.546 troy ounces of pure gold
4. Value at spot ($2,300/oz): 1.546 x $2,300 = $3,555.80 intrinsic gold value

Any price above $3,555.80 represents the jeweler's premium (making charges, profit margin, and local taxes). A premium of 10-20% is standard for hand-crafted bridal jewelry.

Scenario 2: Selling Inherited Gold Bangles in India

Your grandmother left you three 22K gold bangles that the local jeweler weighs at 38 grams total. You want to know the tola weight and fair resale value.

1. Convert grams to tolas: 38 x 0.08573 = 3.258 tolas
2. Convert to troy ounces: 38 / 31.1035 = 1.222 troy ounces
3. Pure gold content (22K): 1.222 x 0.916 = 1.119 troy ounces of pure gold
4. Intrinsic value at $2,300/oz: 1.119 x $2,300 = $2,573.70 USD

When selling, expect to receive 95-98% of the intrinsic gold value from reputable refiners, as they deduct a small refining and assay fee. Use our tola to gram converter to double-check the jeweler's weight claims.

Scenario 3: Comparing a 1 oz Gold Coin vs. a 1 Tola Gold Biscuit

An investor wants to decide between buying a 1 troy ounce Canadian Maple Leaf coin and a 1 tola gold biscuit. The gold content difference matters for portfolio tracking:

• 1 oz Maple Leaf: 31.1035 grams of 24K gold (.9999 fine)
• 1 tola biscuit: 11.6638 grams of 24K gold (.999 fine)
• The Maple Leaf contains 2.6667 times more gold than the tola biscuit
• At $2,300/oz spot: Maple Leaf = $2,300 intrinsic gold value; 1 tola biscuit = $862.50 intrinsic gold value

Common Mistakes When Converting Between Tola, Gram, and Ounce

Even experienced gold buyers make costly conversion errors. Here are the most dangerous mistakes and how to avoid them.

Mistake 1: Confusing Troy Ounce with Avoirdupois Ounce

This is by far the most common and expensive error. The standard (avoirdupois) ounce used in American grocery stores weighs 28.3495 grams. The troy ounce used for gold weighs 31.1035 grams. That is a 9.7% difference. If someone sells you "1 ounce of gold" and delivers 28.35 grams instead of 31.10 grams, you have been shortchanged nearly a tenth of your purchase.

Mistake 2: Rounding the Tola Down to 10 Grams

As explained in detail in our article on the 10-gram tola myth, some unscrupulous jewelers in South Asia use a "rounded" tola of 10 grams instead of the official 11.6638 grams. This gives them a hidden 14.3% discount on the gold they deliver. 1 tola = 11.6638038 grams, never 10 grams.

Mistake 3: Forgetting to Account for Purity

Converting 5 tolas to troy ounces is meaningless for pricing purposes if you do not specify the karat purity. Five tolas of 24K gold (1.875 oz of pure gold) is worth significantly more than 5 tolas of 18K gold (which contains only 1.406 oz of actual gold content, as 18K is 75% pure).

Mistake 4: Using the Wrong Conversion Direction

To convert grams to tolas, you divide by 11.6638 (or multiply by 0.08573). To convert tolas to grams, you multiply by 11.6638. Reversing the operation is a shockingly common mental math error, especially under the pressure of negotiating a purchase in a busy souk. Always double-check with a reliable converter tool.

Mistake 5: Ignoring Currency Conversion When Comparing Cross-Border Prices

A gold price quoted in Pakistani Rupees per tola cannot be directly compared to a price in UAE Dirhams per gram without first converting both values to a common currency and a common weight unit. Investors who skip this step often mistakenly believe gold is "cheaper" in one country when the apparent difference is entirely due to currency valuation.

Tola vs. Gram vs. Ounce for Different Investment Sizes

The unit you focus on should also depend on the scale of your gold investment. Here is a practical guide for different investor profiles.

Small Retail Buyer (Under $1,000)

If you are buying a single piece of jewelry or a small gold coin, you will most commonly deal in grams. Small denominations like 1g, 2g, and 5g gold bars are popular entry-level investments in Europe and Asia. In South Asian markets, a purchase of half a tola to 1 tola (5.8 to 11.6 grams) is the typical first-time buyer range.

Mid-Range Investor ($1,000 - $50,000)

At this level, your unit of choice depends on geography. Western investors typically buy in 1 oz and 10 oz denominations (coins, bars). South Asian investors buy in 1 to 10 tola denominations, with the 10-tola TT bar being the flagship product. In metric markets, 50g, 100g, and 250g bars are popular.

High-Net-Worth and Institutional Investor ($50,000+)

Large-scale buyers operate primarily in troy ounces and kilograms. The COMEX 100 oz bar (approximately 266.67 tolas or 3,110 grams), the LBMA 400 oz Good Delivery bar, and the SGE 1 kg bar are the standard vehicles. At this scale, the tola is rarely used directly, though conversion to tola pricing is still essential for selling into South Asian wholesale markets.

Which Unit Gives the Most Accurate Measurement?

In terms of raw mathematical precision, all three units are equally precise because they are all defined to multiple decimal places. However, there are practical precision differences worth noting.

The Gram's Precision Advantage

Because the gram is the smallest of the three common units, it inherently provides finer granularity when expressing small quantities. A difference of 0.1 grams is clearly visible on a jeweler's scale and represents a meaningful price increment. The same 0.1-gram difference, when expressed in tolas (0.00857 tola) or troy ounces (0.00322 oz), becomes harder to intuit and discuss.

The Tola's Practical Sweet Spot

For jewelry-sized gold purchases in South Asia (typically 5 to 100 grams), the tola provides a convenient middle-ground unit. Expressing a bridal set as "8.5 tolas" is more conversationally natural in that context than saying "99.14 grams" or "3.19 troy ounces."

The Troy Ounce's Institutional Standardization

For large-scale financial reporting, the troy ounce provides the most globally standardized reference point. When a central bank reports it added "50 tonnes of gold reserves," the financial press immediately converts that to troy ounces (approximately 1.607 million oz) for valuation against the spot price. The troy ounce is the universal "financial language" of gold, even if it is not the unit physically stamped on the bar. Explore all the different gold weight units used worldwide for a complete picture.

Which Unit Should You Use as an Investor?

The best unit of measurement depends entirely on what type of gold you are buying and what geographic market you are operating in.

1. The Western ETF and Futures Trader: Use the Troy Ounce

If your strategy involves buying shares of GLD (SPDR Gold Trust), trading options on the COMEX, or buying physical 1-ounce government mint coins (American Eagles, South African Krugerrands) in North America or Europe, you must wire your brain to the troy ounce. The spot price you see online is already denominated in dollars per troy ounce. Trying to convert these prices back into tolas will only add friction to your trading strategy.

2. The Modern Asian / Middle Eastern Wholesale Buyer: Combine Kilograms and Grams

If you are operating a jewelry manufacturing business or buying bulk bullion in markets that have heavily adopted the metric system (like China or increasingly, the UAE institutional level), you should focus on the gram. Buying "Kilobars" (1,000 grams) is the most efficient way to acquire unallocated gold with minimal premiums. You can easily calculate the per-gram spot rate by dividing the ounce spot price by 31.1035.

3. The Traditional South Asian Jewelry & Bullion Buyer: Master the Tola

If you are buying a bridal set in Kerala, investing in TT Bars in Deira's Gold Souk in Dubai, or analyzing daily newspaper gold prices in Lahore, you cannot escape the tola. The local markets literally quote the daily rate as "Price Per Tola."

However, the critical caveat for the tola investor (as explored in our previous blogs) is that you MUST cross-reference the tola rate against the gram rate to ensure you aren't being subjected to round-down scams. Always mathematically verify that the jeweler's "tola" weighs 11.6638 grams and not 10 grams.

Frequently Asked Questions: Tola vs. Gram vs. Troy Ounce

How many grams in 1 tola?

1 tola = 11.6638038 grams exactly. This value was standardized by the British Indian government in 1833 when the tola was defined as the weight of one Indian Silver Rupee coin, minted at exactly 180 troy grains. This conversion factor has remained unchanged for nearly 200 years. You can verify this instantly using our gram to tola converter.

How many tola in 1 ounce?

1 troy ounce = 2.6667 tolas (or exactly 8/3 tolas). Because 1 tola equals exactly 0.375 troy ounces (3/8 of a troy ounce), the inverse gives us 1 troy ounce = 1/0.375 = 2.6667 tolas. This clean fractional relationship exists because both units are defined in terms of troy grains (1 tola = 180 grains; 1 troy ounce = 480 grains).

Which is heavier, 1 tola or 1 ounce?

1 troy ounce is significantly heavier than 1 tola. A troy ounce weighs 31.1035 grams, while a tola weighs only 11.6638 grams. The troy ounce is approximately 2.67 times heavier than the tola. Therefore, 1 troy ounce of gold is worth roughly 2.67 times the price of 1 tola of gold at the same purity level.

Why is gold measured in troy ounces and not regular ounces?

Gold has been measured in troy ounces since medieval European trade fairs in the French city of Troyes, dating back to the 12th century. The troy weight system was specifically designed for precious metals and gemstones, with 1 troy ounce = 480 grains. The "regular" (avoirdupois) ounce, used for everyday goods, equals only 437.5 grains (28.35 grams). The troy system was formally adopted by the English Crown in 1527 and has been the unbroken standard for precious metals trading for nearly 500 years. Changing it now would require rewriting the entire global commodities infrastructure.

How to convert tola to ounce formula?

The formula is straightforward: Troy Ounces = Tola x 0.375. Alternatively, Troy Ounces = Tola / 2.6667. For example, to convert 5 tolas to troy ounces: 5 x 0.375 = 1.875 troy ounces. To convert the other direction (ounces to tola), use: Tola = Troy Ounces x 2.6667, or Tola = Troy Ounces / 0.375. Check your conversions using our tola to gram converter for added confidence.

Can I use regular kitchen scales to weigh gold in tolas?

No. Standard kitchen scales are calibrated in avoirdupois ounces and grams, and typically have a precision of only +/- 1 gram. Gold jewelry requires precision to at least 0.01 grams (10 milligrams). You need a dedicated jeweler's digital scale with milligram precision. Once you have an accurate gram reading, multiply by 0.08573 to get the tola weight, or use our online converter.

Is the tola used for silver as well, or only gold?

The tola is used for both gold and silver across South Asia. In India, Pakistan, and Bangladesh, silver prices are also commonly quoted per tola in local currencies. The tola is a unit of mass, not specific to any one metal. However, silver is also frequently sold in larger denominations (per kilogram), as its lower per-gram price means physical purchases tend to be bulkier.

Conclusion: Bridging the Divide

The global gold market is highly fragmented in its language, but unified in its substance. Whether it is shaped into a 1-ounce coin in a London vault, poured into a 1-kilo bar in Shanghai, or crafted into a 5-tola necklace in a Mumbai storefront, the intrinsic elemental value of Au79 remains identical.

Your ability to seamlessly translate between tolas, grams, and troy ounces acts as a financial shield. It allows you to arbitrage prices across different regional markets, calculate making-charge premiums fairly, and instantly recognize when a vendor's scale simply doesn't add up correctly. Whether you are comparing prices on the COMEX against a local souk, verifying the gold price per tola on a jeweler's LED board, or simply ensuring that the heirloom gold your family has treasured for generations is accurately accounted for, mastery of these three units is indispensable.

For instant, flawless conversions across these boundaries, bookmark our main Gram to Tola interactive calculator to do the heavy lifting for you while you negotiate. And for a quick-reference printout, visit our comprehensive conversion chart.