1 Ounce to Grams: Gold, Butter, Flour & How to Convert

You’ve got a recipe calling for 1 ounce of butter and a gold dealer quoting a price per ounce — but are those the same ounce? The short answer is no, and the difference can cost you. This guide clears up the two‑ounce system so you can convert 1 oz to grams for anything from flour to fine gold.

Standard avoirdupois ounce: 28.35 g ·
Troy ounce for precious metals: 31.1035 g ·
Conversion precision for cooking: 28.35 g ·
Gold price per troy ounce (approx): $1,950 – $2,100 ·
Most common typo: 28 g vs. 32 g

Here are the key figures you need for quick reference.

How many grams is 1 ounce of 24K gold?

What is a troy ounce?

• 1 troy ounce = 31.1034768 grams exactly (The Royal Mint – bullion FAQ)
• 24K gold is pure (99.99% fineness) and is always weighed in troy ounces (Britannica – ounce)
• A troy ounce is about 9.7% heavier than an avoirdupois ounce (Wikipedia – troy weight)

So if you buy a “1 oz gold bar” at a dealer, you’re getting 31.1 grams of precious metal — not the 28.35 grams you’d get from a food scale. The difference matters when comparing prices or calculating portfolio weight.

The implication: using the wrong ounce system can be costly.

Is an ounce 28 or 32 grams?

Avoirdupois ounce (food, general)

• 1 avoirdupois oz = 28.349523125 g (exact) (NIST mass conversion table)
• Rounded to 28.35 g for everyday use (ISWM weights and measures tables)
• Used for body weight, groceries, shipping, and cooking

Troy ounce (gold, silver, platinum)

• 1 troy oz = 31.1034768 g (U.S. Money Reserve – troy ounce)
• About 31.1 g, never 28 g
• Used exclusively for precious metals (Britannica – ounce comparison)

The common confusion — “28 vs 32” — comes from mixing the two systems. A troy ounce is close to 31.1 g, not 32, but rounding to 28 g (for avoirdupois) versus 31 g (for troy) creates a 3‑gram gap that can throw off recipes and investments alike.

Two systems, two numbers. The only way to get it right is to ask: which ounce are we talking about?

How many grams are in 1 ounce of flour or butter?

Converting dry ingredients by weight

• 1 oz butter = 28.35 g (butter is consistent by weight) (NIST conversion)
• 1 oz flour ≈ 28.35 g by weight, but volume depends on compaction (scooped vs. spooned)
• Professional bakers weigh flour rather than use volume to avoid 20% variations – see our butter conversion guide for more precision.

For butter, use 28.35 g per ounce every time. For flour, a kitchen scale reading 28 g is safer than a measuring cup — the density difference between brands can shift the gram count even when the ounce label is correct.

The pattern: weight accuracy is critical in baking.

How much is 1 ounce of gold worth now?

Where to check live gold price

• Gold price fluctuates daily; it is always quoted per troy ounce (London Bullion Market Association – LBMA)
• Typical sources: LBMA, Kitco, Bloomberg
• As a reference, 1 troy oz of gold was approximately $2,050 in early 2025 (example only)

Because gold is priced per troy ounce, you can multiply the spot price by 1.097 to get the cost per avoirdupois ounce — useful if you’re comparing a gold bar to a household object.

Two ounces, two gram counts. Here’s how they stack up head‑to‑head.

One ounce, multiple precision levels. Choose the right factor for your context.

How to convert 1 ounce to grams: step by step

1. Identify the ounce type. Is it a recipe (avoirdupois) or precious metal (troy)? Ask the label or seller. Britannica advises checking the context.
2. Pick the conversion factor. Avoirdupois → 28.35 g per oz. Troy → 31.1 g per oz. Use the exact values from NIST for precision.
3. Multiply. Number of ounces × factor. Example: 2 oz butter × 28.35 = 56.7 g.
4. Round if needed. For cooking, round to 0.1 g. For gold, use two decimals (31.10 g).
5. Verify with a calculator. Use an online ounce‑to‑gram converter for double‑checking, especially for large amounts.

The catch: if you skip step 1 and assume every ounce is the same, you’ll be off by up to 9.7%. For a gold purchase, that’s hundreds of dollars.

Is it smart to buy 1 oz of gold?

Pros of buying a 1 oz gold bar or coin

• High liquidity – 1 oz gold coins and bars are widely traded and easy to sell.
• Low premium over spot – smaller bars often carry higher premiums.
• Easy to verify – weight, purity, and dimensions are standardised.

Buying 1 oz of gold in a recognised bar or coin from a reputable dealer is a straightforward entry point for investors. As always, confirm the seller uses troy ounces and check the current spot price.

What we know and what’s still fuzzy

What this means: check the ounce type every time.

“The avoirdupois ounce is officially defined as 28.349523125 grams.”

— NIST (National Institute of Standards and Technology), U.S. measurement authority

“Good delivery gold bars are traded in troy ounces.”

— London Bullion Market Association (LBMA), global precious‑metals benchmark

For anyone buying gold, one ounce means 31.1 grams — not 28.35. For cooks and bakers, the opposite is true. The trade‑off is simple: use the wrong ounce system and your recipe flops or your investment loses nearly 10% of its expected weight. For the home chef measuring butter, the choice is clear: stick with avoirdupois (28.35 g per oz) and weigh your ingredients. For the gold buyer, insist on troy ounces and check the spot price before you commit.