ISO 1832 Tools and Reference Tables

Decode a designation

• ISO 1832 decoder — paste CNMG120408, WNMG080404 or an ANSI code such as CNMG432 and read every position: shape, clearance, tolerance, fixing, inscribed circle, thickness, nose radius and hand. Runs in the browser; nothing is sent to a server.
• Cross reference finder — check whether two catalogued models are geometrically interchangeable, with each cited brand code behind the verdict.
• Embed the decoder — the same decoder as a free iframe for engineering sites and forums. One line of code, no sign-up.

Look up a code

• Shape, clearance, tolerance and fixing codes — every letter in positions 1–4 plus the optional hand in position 8, with the catalogued inserts that use each one and a top-view gallery of the shapes. Useful when you know the letters but not what they permit.
• ISO 1832 size code chart — what each two-digit size block means for every insert shape. The same code gives a different inscribed circle on a rhombic and a 35° V body, and the chart shows both.
• Thickness and nose radius codes — position 6 selects a standardised thickness (04 is 4.76 mm, not 0.4 mm) while position 7 counts tenths of a millimetre directly (08 is 0.8 mm). Both tables are decoded side by side.
• ANSI insert code index — every cited three-digit shop-floor code and the ISO designation it converts to, grouped by shape.
• Dimension set index — browse the inscribed circle × thickness × nose radius combinations that manufacturers actually publish.

How the tools relate to the data

Each tool is a view over the same two layers. The geometry layer is the published ISO 1832 code tables; the catalogue layer is the brand ordering codes cited on each model page. The decoder and the charts work from the geometry layer only, so a result never depends on a particular manufacturer's naming. The cross reference finder is the one tool that combines both, and it reports the level of confirmation — full geometry match, partial match, or verify against the catalogue — instead of assuming interchangeability.

If a designation is missing from a table, it is because the standard value or the catalogue row is not confirmed yet, not because it was rounded or estimated. The editorial and correction policy explains how entries are verified and how to report one that is wrong. For the reading behind these tables, start with the ISO 1832 designation walkthrough.