Tolerance
- Category /
- Tolerance & Measurement
- Also called /
- tolerancing, tol
- Related /
- 4 terms
- Source /
- Written in the shop
Tolerance is the amount a finished dimension is allowed to differ from the dimension on the drawing and still be accepted.
Also called: tolerancing · tol
In practice
Every manufactured dimension varies. A tolerance states how much variation the part can carry and still work — written as a plus/minus band (2.500" ±0.002") or as limits (2.498"–2.502"). Tighter is not better; tighter is more expensive, and a tolerance that is tighter than the function requires is money spent for nothing.
Why it matters
Tolerance is the single biggest driver of machining cost after material. Loosening a non-critical dimension from ±0.001" to ±0.005" can change which machine runs the job, whether a second operation is needed, and how many parts get scrapped.
More in Tolerance & Measurement
Have a drawing with this on it?
Send it over and we will tell you what it will take to hold — and what is safe to loosen.