Free Machinist Reference Charts

Quick, ad-free reference charts for machinists, CNC operators, students and DIY metalworkers. Every chart is also available as a clean printable PDF.

Tap Drill Chart
UNC, UNF & Metric Tap Drill Sizes

Drill Size Chart
Number, Letter, Fraction & MM

Decimal Chart
Fraction to Decimal to MM

Thread Chart
UNC/UNF TPI, Metric Pitch, NPT

Speeds & Feeds
RPM and Feed Calculator

G-Code List
Common CNC G & M Codes

GD&T Symbols
Meaning of Each Symbol

Want them all on paper?
Tap drill, G-code, checklist, decimal, speeds & feeds and GD&T sheets in one download.