FREE CNC TOOLS · Handy shop-floor utilities

CNC Machining Tools

8 free calculators and reference charts for the shop floor—no sign-up, mobile-friendly, nothing uploaded. Built on the same engineering basis as our 69 technical articles.

CALCULATOR

Cutting Speed / RPM / Feed Calculator

Enter Vc and cutter diameter to get RPM; enter flute count and fz to get feed rate. Includes a Vc reference table for common materials.

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CHART

Tap Drill Size Chart

Recommended drill sizes for M2–M30 metric coarse/fine threads, with a quick formula and adjustments for hard-to-machine materials.

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CALCULATOR

Metal Weight Calculator

Plate / round bar / tube / hex bar × common material densities—essential for stock estimating.

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CHART

Surface Roughness Chart

Ra / Rz / N grade / ▽ symbol cross-reference plus the Ra range each process can achieve.

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LOOKUP

ISO Tolerance Lookup

Enter a size, pick IT5–IT13, and read the ISO 286 standard tolerance value instantly.

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CONVERTER

Inch ↔ mm Converter

Two-way conversion plus a 1/64″–1″ fractional-inch table, computed exactly to 25.4.

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QUICK REFERENCE

G-code / M-code List

Quick lookup of common FANUC codes with live search; controller-dialect differences are flagged.

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CALCULATOR

Taper Calculator

Compute taper ratio and angle from large/small diameter and length, with a table of common tapers such as 7:24.

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All tools are free and require no sign-up; calculations run locally in your browser and nothing is uploaded. Engineering data uses standard formulas and common table values, with any approximate conversions clearly flagged; before running, always confirm against your tool supplier's catalog and shop-floor conditions. To be notified when new tools launch or to request one, drop us a message.

TOOLS ARE JUST THE START

Beyond lookups and calculators—let AI turn your drawing straight into a verifiable machining program

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