CNC Machinist Calculator +

Speeds and feeds, tap drill sizes and bolt-circle coordinates in one shop calculator — imperial or metric, works offline.

▶ Every shop calc in one app. Get speeds and feeds, tap drill sizes and bolt-circle coordinates without flipping through charts or paying for a locked-up tool.

▶ Speeds & feeds, both ways. Pick a material and enter tool diameter and flute count for RPM, cutting speed and feed rate — or work it backward from RPM. Switch imperial and metric anytime.

▶ Tap drill in seconds. Choose a metric or unified thread and get the tap drill size with the nearest standard drill, plus a thread-percentage slider for tight or loose fits.

▶ Bolt circle coordinates. Enter hole count, diameter and start angle for an X/Y table you can copy row by row straight into the control, with a quick preview.

▶ Reference built in: material speed presets, a number/letter/fraction/metric drill chart, point-depth and surface-finish cards.

Recommended speeds are a starting point, not a final spec. Tune to your machine, tooling and material, and follow your tooling maker's data.