Build stuff?  Well then you need Wonderbolt.



Designed to be the fastest and easiest way to measure, identify, and cross-reference threaded fasteners, Wonderbolt gives craftspeople of any skill level the upper hand

The Facts:

What can Wonderbolt do for you?

 For both US and Metric…

Wonderbolt lets you:

  • Measure outer diameter
  • Measure Length
  • Determine thread count
  • Save and annotate sizes for later
  • Determine correct measurements for online purchases

Wonderbolt gives you:

  • Correct socket or Allen wrench sizes
  • Decimal equivalents, inches and mm
  • Closest Metric or US size
  • Drill bit sizes for various clearance holes
  • Images for hole size visualization
  • Drill and tap information, hard/soft metals


Right In Your Pocket

Reviews and accolades



I'm always trying to figure out bolt sizes and now I don't have to run to the hardware store every time to figure it out. I love this app!!! My thanks to the developers. You made my life so much easier.


The app helped us get the right bolt without having to spend 30 mins wandering through the fastener aisle.


30 seconds after opening Wonderbolt, I had the right screw. A very satisfying outcome.


The comparisons between Imperial and metric are especially helpful. Definitely worth purchasing this app.


Measure fast. Build more. Swear less.

A must-have in anyone’s tool kit.

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