About Measure Screw

Updated September 27, 2026

Measure Screw helps you measure screw size and compare common fastener types using straightforward tools and reference charts.

What you can do here

Calibrate an on-screen gauge with a payment card or ruler, estimate a screw’s diameter and length, or enter readings from your own measuring tools. Compare nearby metric and US machine screw sizes, check common pitches, and use visible tip and thread features to narrow down a screw family.

How we present results

Our results are estimates and reference information. The closest diameter is not a confirmed identification. Thread pitch, length, head shape, material and the intended application all matter. Screen measurement depends on correct calibration and display settings.

Reference information

The US size chart draws on the Monster Bolts screw-size reference. Measure Screw is an independent tool and is not presented as affiliated with that supplier. Charts cover common sizes, not every fastener standard or specialty thread.

Our approach

We aim to make measurement instructions clear, show the limitations of visual identification and avoid suggesting that similar sizes are interchangeable. Use calibrated physical tools and the original manufacturer’s specification when exact fit matters.