Machinist Tools
Free online calculators and reference charts — built for the shop floor
Tap Drill Chart
Searchable tap drill chart with UNC, UNF, and metric thread sizes. Find the right drill size for any thread instantly.
Open Tool →Unit Converter
Convert between fractions, decimal inches, and millimeters. Includes a full reference table from 1/64" to 1".
Open Tool →Drill Size Chart
Complete reference of all Number, Letter, Fractional, and Metric drill sizes with decimal and millimeter equivalents.
Open Tool →Built for the Shop Floor
These tools are designed for machinists who need quick answers while working. Large touch targets, instant results, and no unnecessary clicks. Use them on your phone with greasy hands — they just work.