Gold by Weight Calculator
Estimate melt value from weight, karat, and current spot price.
How this gold by weight calculator works
A gold by weight calculator estimates the raw metal value (also called melt value) of your jewelry, coins, or scrap gold. It does this in three steps: convert the item into grams, adjust for purity using karat, and multiply the pure gold weight by the current gold spot price.
This tool is helpful if you want a quick estimate before selling gold, comparing buyer offers, or evaluating whether an item is worth refining. It does not include collectible premiums, craftsmanship value, brand markup, or assay fees.
Formula used
1) Convert your item to grams
Different items are weighed in different units. We convert everything to grams first, then to troy ounces for pricing.
- 1 troy ounce = 31.1034768 grams
- 1 avoirdupois ounce = 28.349523125 grams
- 1 pennyweight (dwt) = 1.55517384 grams
2) Adjust for gold purity
Karat tells you what fraction of the piece is pure gold: purity = karat / 24. For example, 18K gold is 18/24 = 75% pure.
3) Compute melt value
Pure gold content in troy ounces × spot price per troy ounce = melt value. If you add a payout percentage (like 85%–95%), you also get an estimated dealer offer.
Why payout percentage matters
Most local buyers do not pay 100% of melt value. Their quote must cover testing risk, operating costs, market movement, and profit margin. Typical payout ranges:
- Pawn shops: often lower percentage of melt value
- Mail-in gold buyers: moderate, varies by company
- Refiners / high-volume buyers: often highest payouts for larger lots
Example calculation
Suppose you have a 25g bracelet marked 18K, spot price is $2,200/ozt, and expected payout is 90%.
- Weight in grams: 25g
- Purity: 18/24 = 0.75
- Pure gold: 25 × 0.75 = 18.75g
- Pure gold in troy ounces: 18.75 ÷ 31.1034768 = 0.6028 ozt
- Melt value: 0.6028 × 2200 = $1,326.16
- Estimated offer at 90% payout: $1,193.54
Tips before selling gold
- Separate items by karat (10K, 14K, 18K, etc.).
- Weigh pieces accurately on a digital scale.
- Check the live spot price right before requesting quotes.
- Get multiple offers from different buyers.
- Ask whether fees, shipping, or assay charges are deducted.
Common mistakes to avoid
Using regular ounces instead of troy ounces
Precious metals are priced in troy ounces, not kitchen-scale ounces. Mixing these units can create a major pricing error.
Ignoring non-gold components
Stones, clasps, and mixed-metal parts reduce pure gold content. The final payout may be based on recoverable metal after inspection.
Assuming collectible pieces are worth only melt
Some coins and branded jewelry may be worth much more than melt value due to rarity, condition, or demand.
Quick FAQ
Is this calculator accurate?
It is accurate for an estimate when your inputs are accurate. Final offers can vary after testing and verification.
Can I use this for white gold or rose gold?
Yes. If the karat is known, the gold content calculation works the same way.
Does this include taxes or dealer fees?
No. Use the payout percentage to model typical deductions in one simple input.