The scale is simpler than it looks
US coin grading runs on the Sheldon scale: 1 through 70, where 1 is barely identifiable and 70 is perfection under magnification. In practice you only need the named waypoints, and each has a plain-English meaning:
| Grade | What it means |
|---|---|
| AG-3 (About Good) | Heavily worn; outline and date barely readable |
| G-4/G-6 (Good) | Major design outlined, rims mostly full, details flat |
| VG-8 (Very Good) | Major design elements clear but flat |
| F-12/F-15 (Fine) | Moderate even wear; finer detail visible |
| VF-20–35 (Very Fine) | Light wear on high points; most detail present |
| EF-40/45 (Extremely Fine) | Light wear, sharp detail, traces of luster possible |
| AU-50/58 (About Uncirculated) | Trace of rub on the highest points only |
| MS-60–70 (Mint State) | Never circulated; no wear, only contact marks and luster quality separate the numbers |
How to practice on your own coins
- Work one series at a time — grading calibrates fastest when the design is constant. Lincoln cents are the classic training ground.
- Learn the high points of that design first: they wear first, and their condition sets the grade ceiling.
- Compare against graded photos: PCGS and NGC publish photograde guides online, free.
- Grade the coin, then the surfaces: scratches, cleaning, and repairs are noted separately from wear and cut value independently.
Two traps that cost the most money
Cleaning — a wiped coin can look better to a beginner and be worth dramatically less forever. And "problem-free" pricing — price guides quote problem-free coins; your cleaned, scratched, or holed example is worth a fraction of guide.
Why grading is the hobby's core skill
Every value question — an inherited collection, a dealer's offer, a fair trade — resolves to "which grade?" Learning to grade well is what lets you buy and keep coins with confidence, and it is entirely learnable with time and cheap coins.