M7 Bolt Size and Thread Specifications
Quick answer
M7 bolts use 7mm major diameter with 1.0mm coarse pitch in common references.
They sit between M6 and M8 in diameter for specialty hardware lines.
Use the tables here and the thread identifier when prints or samples disagree.
M7 is less common than M6 or M8 but appears in some European equipment and specialty hardware. Confirm availability of matching nuts and wrenches before specifying. Spanish reference: perno M7. For tap drill size, thread types, and thread identifier workflows, pair this page with tools as you verify threads.
Specifications
| Specification | Value |
|---|---|
| Nominal diameter | 7 mm |
| Standard pitch (coarse) | 1.0 mm |
| Fine pitch | 0.75 mm |
| Tap drill size | 6.0 mm |
| Closest imperial equivalent | between M6 and 1/4" |
Hex head size
| Bolt size | Hex head size |
|---|---|
| M7 | 11 mm |
Common uses
Special mechanisms, some bicycle components, and replacement parts that call out M7 on drawings. Cross-check loads with the bolt size chart and screw size conversion when you mix metric and inch bins.
Related tools
Related charts
M7 vs M8 bolt size
Shank diameter and pitch set tap drill, hex key, and strength for each ISO size. Compare values in the tables above with the M8 bolt size page when you resize hardware.
Use the bolt size chart when you compare hex and shank columns across sizes.
Metric vs UNC thread size
Metric threads list diameter in millimeters and pitch in millimeters per thread; UNC lists nominal inch diameter and threads per inch. They are not interchangeable—taps, dies, and gauges differ.
Read metric vs unc thread context when series labels are unclear.
Use screw size conversion when you must match stocked parts.
M7 specifications and tools
How to choose the right bolt size
Choosing the correct bolt size depends on load, material, and thread type. Larger diameters increase strength, while thread pitch affects holding force.
Use the bolt size chart to compare shank and hex dimensions before you standardize hardware.
Use tap drill size guidance when you plan tapped holes.
Use the thread identifier when stamped sizes are missing.
FAQ
What is the standard pitch for an M7 bolt?
The common coarse pitch for M7 is 1.0 mm. Fine pitch is often 0.75 mm where specified.
What drill size should be used for tapping M7 threads?
For M7 x 1.0 coarse thread, use approximately a 6.0 mm tap drill. Use our Tap Drill Calculator for other pitches.
What imperial fastener is closest to M7?
between M6 and 1/4" is a practical reference for comparing M7 to inch hardware; verify fit for your application.