F4 Wiki

A trusted GD&T reference with F4 validation behavior, reviewed and published by moderators.

This wiki is the public, stable reference for how GD&T concepts are defined and how the F4 Application interprets and validates them. Every page links standard guidance to F4-specific behavior so engineers can move from definition to decision quickly.

Quick start

for standard definitions and examples.
for validation rules, warnings, and errors.
for short definitions.
for worked applications.
Community forum for discussions and questions.

How to use this wiki

The public view shows approved revisions only.
Each GD&T page links to its matching F4 validation page.
Use the sidebar or search to find topics quickly.
When an item requires interpretation, the F4 page calls out the decision and how it affects compliance.

About F4

F4 is an engineering platform focused on GD&T interpretation and compliance checks. Use this wiki alongside the official docs and downloads.

Featured pages

Contribute