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An App for Finding Varieties, Errors, and Die Identifications.

Maxvan1Maxvan1 Posts: 189 ✭✭✭
edited September 6, 2026 2:29PM in U.S. Coin Forum

I hope sharing this type of thing is allowed here.

I made a free web app for viewing, comparing, and diagnosing coins. It is useful for finding varieties, errors, die matches, and for general side-by-side comparison.

You can load up to 20 coins at once with the zoom locked, so they stay aligned while you pan and zoom. PCGS and CACG photos are auto-sized so the comparison is faster. You can annotate, mark, measure, point, rotate, use layers, blink-compare, change opacity, and export with notes.

How to load coins:

  • Best method: drag and drop photos from your desktop, or enter individual PCGS cert numbers with your own PCGS API key
  • CACG low-res bulk import by cert number usually works, but the photos come in as cropped banner images
  • TrueView bulk import is still in beta and usually fails. Do not use it. It will burn through your daily API calls.

Individual PCGS imports take about 20 seconds per cert.

App: https://diebench.grok.me

100% free, no ads. No association with any company or person involved with grading or numismatics.

Comments

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    IkesTIkesT Posts: 4,611 ✭✭✭✭✭

    @Maxvan1 said:
    100% free, no ads. No association with any company or person involved with grading or numismatics other than myself.

    FTFY

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    Maxvan1Maxvan1 Posts: 189 ✭✭✭

    @IkesT said:

    @Maxvan1 said:
    100% free, no ads. No association with any company or person involved with grading or numismatics other than myself.

    FTFY

    Thanks. I'll make that change.

    Feedback greatly appreciated. This took significant time and effort to build and I'm offering it for free.

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    Maxvan1Maxvan1 Posts: 189 ✭✭✭

    Open to feature requests.

    Currently in the works:

    • AI analyze will be added soon. The AI (Grok) will compare the current cropped photos and tell to user whether and which dies are matching, listing all relevant die markings and places to look under a loupe.
    • AI doubling die detection and clash detection.
    • Auto measure die face rotation based on slab photos.
    • Auto measure rim width at 1, 2, 3, 4... 11, 12 o'clock.
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    The_Dinosaur_ManThe_Dinosaur_Man Posts: 1,594 ✭✭✭✭✭

    Is the Cherrypickers Guide not good enough?

    Custom album maker and numismatic photographer.
    Need a personalized album made? Design it on the website below and I'll build it for you.
    https://www.donahuenumismatics.com/.

  • Options
    Maxvan1Maxvan1 Posts: 189 ✭✭✭

    @The_Dinosaur_Man said:
    Is the Cherrypickers Guide not good enough?

    Name fits. Sorry. :D

    Use Cherrypickers to figure out what you're hunting. Use this to hunt for it.

    Ebay integration coming soon. Paste the listing, pull up the pictures, and quickly compare with the library.

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    DesertCoinDesertCoin Posts: 484 ✭✭✭

    Fascinating, thank you for the share.

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