NumisDex
Whether you hear “New Mistakes,” “No Mistakes,” or “Numismatics + Index” — you're correct.
Discover. Collect. Connect.
The Platform Built for Coin Collectors.
NumisDex is where collectors explore 72,000+ coin varieties and errors, track their portfolios, learn from experts, and join a growing community — all in one place. Free forever.
Everything a Collector Needs
More than a database — NumisDex is the all-in-one platform for the modern numismatist.
Explore the Catalog
72,000+ expert-attributed varieties and errors across every U.S. series
Track Your Portfolio
Organize multiple collections, import via CSV, share or keep private
Join the Discussion
Community forums for every topic — from die varieties to market trends
Learn & Level Up
Explore our Learn section with guides on varieties, grading, and attribution
Contribute & Vote
Submit discoveries, vote on attributions, and help build the definitive reference
This week2–8 November 2026
A Leaf Nobody Can Explain, Rim Cuds vs. Cuds, a Clash the Size of a Portrait, and Ike Goes to the Moon
The Wisconsin quarter's mystery leaf, how to tell a rim cud from a cud, a 1935 cent with Lincoln's whole portrait clashed into the back, and the dollar coin that carried the Moon landing.
See this week's coins→Built by Collectors, for Collectors
NumisDex isn't just a reference — it's a community. Track your collection, message other collectors directly, earn recognition for your expertise, and help build something that lasts.
Portfolio Tracking
Manage multiple collections with privacy controls
Direct Messaging
Connect one-on-one with collectors and experts
Numiscore & Leaderboards
Earn recognition as you contribute to the community
Guided Onboarding
Get started fast with interactive walkthroughs
