📐 Bevel Angle Calculator
Enter the blade thickness and bevel width in millimetres to work out the edge angle — degrees per side and the total inclusive angle — so you can match your sharpening setup to the grind.
📐 From Geometry to Edge Angle
What is a Bevel Angle Calculator?
It derives the angle of a knife's cutting edge from two measurements: how thick the blade is and how wide the ground bevel is. Using basic trigonometry it returns the per-side angle and the total inclusive edge angle, so you can see exactly how a blade was ground.
That's useful when you want to reproduce an existing edge on a whetstone rather than guess — matching the factory angle means removing less metal and keeping the edge consistent. It's a geometric estimate, so measure carefully and treat the result as a close guide.
❓ Frequently Asked Questions
How does it calculate the bevel angle?
It treats the bevel as a right triangle: half the blade thickness is the opposite side and the bevel width is the adjacent side. The per-side angle is the arctangent of that ratio, and doubling it gives the total inclusive edge angle. Both are rounded to one decimal place.
How do I measure blade thickness and bevel width?
Measure the blade thickness just above the bevel with calipers, and the bevel width across the ground face from the shoulder down to the very edge. Both in millimetres. Small measurement errors change the result, so measure carefully and take the figure as a close estimate.
Why would I calculate an existing bevel angle?
Knowing the angle a knife was ground to lets you match it on the stone instead of guessing, so you reshape less metal and keep a consistent edge. It's also a handy sanity check against the angle a maker advertises.