Decode any carbide insert designation. Type CNMG 432 or WNMG 080408 and see what every character means, with insert shape visualization and complete reference tables for ISO and ANSI standards.
Last updated April 2026
| C | 80 deg Diamond (80 deg) |
| D | 55 deg Diamond (55 deg) |
| R | Round (360 deg) |
| S | Square (90 deg) |
| T | Triangle (60 deg) |
| V | 35 deg Diamond (35 deg) |
| W | 80 deg Trigon (80 deg) |
| K | 55 deg Parallelogram (55 deg) |
| N | 0 deg (negative rake) |
| A | 3 deg |
| B | 5 deg |
| C | 7 deg |
| P | 11 deg |
| D | 15 deg |
| E | 20 deg |
| F | 25 deg |
| G | 30 deg |
| A | +/-0.001" IC, +/-0.001" thickness |
| C | +/-0.001" IC, +/-0.001" thickness |
| G | +/-0.001" IC, +/-0.005" thickness |
| H | +/-0.0005" IC, +/-0.001" thickness |
| M | +/-0.002-0.005" IC, +/-0.005" thickness |
| U | +/-0.005-0.012" IC, +/-0.012" thickness |
| J | +/-0.002-0.003" IC, +/-0.005" thickness |
| K | +/-0.002-0.005" IC, +/-0.005" thickness |
| L | +/-0.002-0.005" IC, +/-0.005" thickness |
| A | No hole, no chipbreaker |
| G | Hole with chipbreaker (both sides) |
| M | Hole, no chipbreaker |
| N | No hole, no chipbreaker (same as A) |
| T | Hole with chipbreaker (one side) |
| W | Wiper geometry |
| F | Hole, chipbreaker one side (sharp edge) |
| Q | Hole, chipbreaker both sides (with wiper) |
| 1 | 1/8" (0.125") |
| 2 | 1/4" (0.250") |
| 3 | 3/8" (0.375") |
| 4 | 1/2" (0.500") |
| 5 | 5/8" (0.625") |
| 6 | 3/4" (0.750") |
| 1 | 1/16" (0.0625") |
| 2 | 1/8" (0.125") |
| 3 | 3/16" (0.1875") |
| 4 | 1/4" (0.250") |
| 5 | 5/16" (0.3125") |
| 6 | 3/8" (0.375") |
| 0 | Sharp (no radius) |
| 1 | 1/64" (0.015625") |
| 2 | 1/32" (0.03125") |
| 3 | 3/64" (0.046875") |
| 4 | 1/16" (0.0625") |
| 5 | 5/64" (0.078125") |
| 6 | 3/32" (0.09375") |
| 8 | 1/8" (0.125") |
| Designation | Decoded | Common Use |
|---|---|---|
| CNMG 432 | 80 deg diamond, 0 deg clearance, medium tol, hole+chipbreaker, 1/2" IC, 3/16" thick, 1/32" nose | General turning, roughing to semi-finish on steel and stainless |
| WNMG 432 | 80 deg trigon, 0 deg clearance, medium tol, hole+chipbreaker, 1/2" IC, 3/16" thick, 1/32" nose | Copy turning, profiling, good for contours |
| DNMG 432 | 55 deg diamond, 0 deg clearance, medium tol, hole+chipbreaker, 1/2" IC, 3/16" thick, 1/32" nose | Finishing and semi-finishing with good reach |
| VNMG 332 | 35 deg diamond, 0 deg clearance, medium tol, hole+chipbreaker, 3/8" IC, 3/16" thick, 1/32" nose | Fine profiling and finishing, tight corners |
| SNMG 432 | Square, 0 deg clearance, medium tol, hole+chipbreaker, 1/2" IC, 3/16" thick, 1/32" nose | Heavy roughing, 8 cutting edges for economy |
| TCMT 21.51 | Triangle, 7 deg clearance, medium tol, hole+chipbreaker one side | Light finishing, boring bars |
| CCMT 32.51 | 80 deg diamond, 7 deg clearance, medium tol, hole+chipbreaker one side, 3/8" IC | General purpose boring and turning |
Click a row to decode it
CNMG 432 is an ANSI insert designation. C = 80-degree diamond shape, N = 0-degree relief angle, M = +/- 0.005" tolerance class, G = chipbreaker/hole configuration. The 432 suffix means 1/2" inscribed circle (4), 3/16" thickness (3), and 1/32" nose radius (2). ISO equivalent is CNMG 120408.
The first letter defines the insert shape. C is an 80-degree diamond and W is a trigon (80-degree hexagonal shape with three usable corners). WNMG inserts have a larger included angle per corner, making them stronger for heavy roughing. CNMG is more versatile for profiling and finishing due to better clearance at acute approach angles.