Gold Weight Calculator - CalcHub

Gold Weight Calculator

Calculate the true value of your gold jewelry, coins, or scrap. Supports Troy Ounces, Grams, Pennyweight, and Tola.

$

Enter current live spot price of gold.

%

100% = Market Value. Cash-for-gold shops pay 70-80%.

How to Use This Calculator

  1. Weigh Your Gold: Use a precise scale to weigh your item. Kitchen scales are okay for rough estimates, but jeweler's scales are best.
  2. Select Unit: Choose the unit you weighed in. Grams is most common, but Pennyweight (dwt) is often used in the US jewelry trade.
  3. Identify Karat: Check the stamp on your jewelry (e.g., 14k, 585, 750). Select the matching purity.
  4. Check Spot Price: The calculator has a default market price, but gold fluctuates minutely. For 100% accuracy, Google "current gold spot price" and enter it.
  5. Set Payout (Optional): If you are selling to a shop, they need to make a profit. Click "Set to Scrap" to see a realistic offer (usually 80% of market value).

How This Calculator Works

This calculator determines the value of your gold items using a standard appraisal formula used by jewelers and scrap buyers. It processes your input in four specific steps:

  1. Unit Conversion: First, it converts your input weight (whether in Ounces, Pennyweight, or Tola) into a standardized metric weight (Grams).
  2. Purity Adjustment: It calculates the percentage of actual gold in your item based on the Karat you selected. For example, 14K gold is only 58.3% pure gold, while the rest is alloy.
  3. Pure Weight Calculation: It multiplies the total weight by the purity percentage to find the "Pure Gold Weight." This is the only part of the item that holds monetary value.
  4. Value Estimation: Finally, it multiplies the pure weight by the current market spot price per gram. If you set a "Payout Percentage" (e.g., 80%), it applies that factor to show you a realistic cash offer rather than the raw stock market value.

Gold Weight Formula

To calculate the pure gold value manually, you can use the following standard formula:

Value = (Weight × (Karat ÷ 24)) × Price per Unit

  • Weight: The total weight of your item.
  • Karat ÷ 24: This calculates the purity decimal (e.g., 18K ÷ 24 = 0.75 or 75% pure).
  • Price per Unit: The current market price for that specific weight unit (e.g., price per gram).

Gold Purity Reference Chart

Swipe table to view details
Karat Purity % Hallmark / Stamp Common Use
24K 99.9% 999 Bullion Bars, Coins
22K 91.6% 916 High-End Jewelry (Asia/India)
18K 75.0% 750 Fine Jewelry, Watches
14K 58.3% 585 Standard US Jewelry
10K 41.7% 417 Durable/Budget Jewelry
9K 37.5% 375 Vintage/Antique (UK/Europe)

Note: Purity determines the value. Stamps (hallmarks) are usually found on the inside of rings or clasps.

Example: Using the gold weight calculator

Let's calculate the scrap value of an old 14K gold ring that weighs 5.2 grams. Assume the current market spot price is $2,650.00 per ounce and the scrap dealer pays 80%.

  1. Select the Unit from the list as Grams (g).
  2. Enter the Gold Weight as 5.2.
  3. Select the Purity as 14K (58.3% Pure).
  4. Ensure the Current Market Spot Price is set to $2,650.00.
  5. Set the Payout Percentage to 80 (for scrap value).
  6. The calculator will automatically determine the Total Estimated Value as $206.75.

Pure Gold Weight = Total Weight × Purity
= 5.2g × (14 ÷ 24) = 3.033 grams

Price Per Gram = Spot Price ÷ 31.1035
= $2,650 ÷ 31.1035 ≈ $85.20 / g

Final Value = Pure Weight × Price/g × Payout %
= 3.033g × $85.20 × 0.80 = $206.75

Understanding Gold Value: Karats & Units

Valuing gold isn't just about weight; it's mostly about purity. Pure gold is too soft for most jewelry, so it is mixed with other metals like copper, silver, or zinc to create an alloy. The "Karat" (K) system measures this purity out of 24 parts.

Common Karat Stamps

  • 24K (99.9%): Pure gold. Usually found in investment bars or coins, rarely in jewelry due to softness.
  • 18K (75.0%): Contains 18 parts gold and 6 parts alloy. Common in high-end jewelry. Stamp often reads "750".
  • 14K (58.3%): The US standard. 14 parts gold, 10 parts alloy. Durable and affordable. Stamp reads "585".
  • 10K (41.7%): The minimum purity to be legally called "gold" in the US. Very durable. Stamp reads "417".

Troy Ounces vs. Regular Ounces

This is the most common mistake beginners make. Gold is traded in Troy Ounces (ozt), which are heavier than the standard "kitchen" Avoirdupois Ounce (oz).
1 Troy Ounce ≈ 31.1 grams
1 Standard Ounce ≈ 28.3 grams
If you weigh your gold on a standard kitchen scale, you must convert it correctly, or you might overestimate its value by about 10%. This calculator handles that math for you automatically.

Sources & Further Reading:

Frequently Asked Questions

What does the Gold Weight Calculator do?

The Gold Weight Calculator is an easy-to-use digital tool that helps you calculate the true value of your gold items. It takes the weight of your gold in different units (such as grams, pennyweight, or troy ounces), adjusts for purity and karat, converts everything using standardized conversion formulas, and then uses the current market price to display an estimated payout or market value.

Which units of weight can I use in the calculator?

You can weigh and input your gold measurement in several units: Grams, Troy Ounces, Pennyweight (dwt), and Tola. The calculator then automatically converts everything into grams using internal density and conversion factors. This makes your result more accurate and standardized, whether you’re valuing a small piece of jewelry, a coin, or a gold bar.

How do I find and select the correct gold purity (karat)?

Look for the stamp or hallmark on your jewelry or gold item (for example 999, 916, 750, 585, 417). This mark tells you the karat and purity of the precious metal. In the calculator, simply select the matching karat value (like 14K or 18K), and the tool will use the correct purity percentage when it computes your gold’s value.

What is the “Current Market Spot Price” and how do I get it?

The spot price is the live market price of pure gold per troy ounce. Because gold is a precious and highly traded metal, this number changes all the time. For an accurate calculation, you can quickly check any financial site or compare multiple sources, then input the current spot price into the calculator. The tool will automatically convert that troy-ounce price into a per-gram rate.

What does the “Payout Percentage” mean?

The Payout Percentage tells the calculator how much of the full market value you are likely to receive when selling your gold. Scrap buyers and shops need to cover refining, handling, and risk, so they don’t pay 100% of the spot price. By adjusting this field (for example to 80%), you ask the tool to estimate a more realistic, real-world cash offer for your gold weight, whether it’s loose scrap, a broken chain, or refined bars and coins.

How is the pure gold weight calculated from my item?

First, the digital calculator takes your total weight and converts it into grams if needed. Then it applies the purity based on the selected karat. The formula is: Pure Gold Weight = Total Weight × (Karat ÷ 24). This step allows the tool to determine how much refined, precious metal is actually in your ring, necklace, coin, or bar, which is essential for a precise value calculation.

How does the calculator turn my gold weight into a final value?

The process is broken into a few intuitive steps:

  • The tool takes your measurement in grams, ounces, or other units and automatically converts it into grams.
  • It uses the selected purity and karat to calculate the pure gold weight.
  • From the spot price per troy ounce, it computes a standardized price per gram.
  • Finally, it multiplies pure gold grams by the per-gram price and applies your chosen payout percentage to display the final estimated value.

This workflow makes it a reliable, standardized way to estimate your gold’s worth.

What’s the difference between a Troy Ounce and a regular ounce?

A troy ounce is a special unit used to measure precious metals like gold and silver. It is heavier than a regular kitchen ounce:

  • 1 Troy Ounce ≈ 31.1 grams
  • 1 Standard Ounce ≈ 28.3 grams

If you use a regular kitchen scale and treat standard ounces as troy ounces, you will overestimate your gold’s value. The gold weight calculator corrects this automatically by using the proper conversion, giving you more accurate and precise results.

Can I use a kitchen scale to weigh my gold?

Yes, you can weigh your gold on a kitchen scale, especially if it shows grams. Many people use this as a quick, portable and lightweight option. However, for very small pieces of jewelry or fine bars and coins, a more sensitive, professional jeweler’s scale is recommended. The more precise your measurement, the more reliable and accurate your calculator result will be.

Why is my calculated value higher than what a buyer offers me?

The calculator can show the full market value of your gold if the payout percentage is set to 100%. In real life, gold buyers rarely pay that much, because they must refine the metal, cover overhead, and manage price risk. When you compare your instant digital estimate to a shop’s offer, remember that most scrap dealers pay only a portion of the spot price. To get a more realistic number, simply adjust the payout field to around 70–80% so the tool can estimate what a typical buyer might pay.