Collector Tools

Calculators and converters for numismatic collectors. All calculations happen locally — no data is sent anywhere.

Weight Converter

Convert between troy ounces, grams, avoirdupois ounces, pennyweight, and grains.

Value

Unit

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Convert between karat and millesimal fineness for gold and silver.

Value

Type

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Calculate the metal value based on weight, purity, and current spot price.

Weight

Unit

Purity (fineness)

Spot Price ($/toz)

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Calculate how much over (or under) melt value you paid for an item.

Purchase Price ($)

Melt Value ($)

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Get a rough rarity tier based on mintage numbers. Results vary by coin type and era.

Mintage

Enter a mintage number

Break down grading labels like "PCGS MS65+ CAC" into plain English.

Grade Label

Enter a grade label to decode