Machinist Calculators

Free, professional-grade tools for metalworking calculations. Based on Machinery's Handbook formulas and real-world shop experience.

MILLING & TURNING

⚙PRO

Speeds & Feeds Calculator

The most comprehensive free S&F calculator online. 60+ materials, HSM chip thinning, tool deflection warnings, power requirements, and more.

60+ material presets with SFM ranges
HSM chip thinning compensation
Tool deflection warnings
Spindle power requirements
Shop rules integration

📊

Stock Yield Calculator

Optimize blanks from bar stock. Minimize waste and maximize yield from your raw material.

Calculate parts per bar
Minimize material waste
Cost per part analysis

⬛

Square Diameter Calculator

Calculate the largest square that fits in a round shaft, or required shaft diameter for a given square dimension.

Round to square conversion
Square to round conversion
Visual diagram with waste area
Inches and metric support

⬡

Hexagon Diameter Calculator

Calculate the largest hexagon that fits in a round shaft, or required shaft diameter for a given hexagon dimension.

Round to hexagon conversion
Hexagon to round conversion
Visual diagram with waste area
Inches and metric support

⭕

Bolt Circle Calculator

Calculate Cartesian coordinates for bolt circles with up to 100 holes. Can solve for unknown BC, HD, or MD.

Up to 100 holes supported
Solve for BC, HD, or MD
Cartesian & D.R.O. modes
Visual diagram & coordinates table

🔄NEW

RPM Calculator

Quick spindle speed calculator from SFM and tool diameter. Material presets for HSS and carbide tooling.

Imperial & metric units
HSS / Carbide toggle
Material SFM presets
Quick-select diameters

➡NEW

Feed Rate Calculator

Calculate feed rate (IPM) from RPM, number of flutes, and chip load per tooth.

Material chip load presets
Tool diameter adjustment
IPM and mm/min output
Chip load reference table

🔩NEW

End Mill Calculator

Dedicated end mill speeds and feeds with automatic chip thinning compensation for light radial engagement.

Chip thinning compensation
Flat, Ball, Bull Nose types
MRR calculation
HSS & Carbide presets

🪵NEW

CNC Router Speeds & Feeds

Speeds and feeds for CNC routers — wood, acrylic, MDF, foam, plastics, and composites.

9 router-specific materials
7 bit types with auto-flutes
Max RPM cap warnings
Chip evacuation tips

DRILLING & TAPPING

🔩

Drill Point Depth Calculator

Calculate blind hole depths accounting for drill point geometry. Never bottom out a drill again.

Standard & split-point angles
Visual drill diagram
Common drill size presets
Shop rules warnings

🔧

Tap Drill Size Calculator

Find the right drill size for any thread. Supports UNC, UNF, UNS, UNEF, metric, and NPT pipe threads with adjustable engagement.

140+ thread sizes

Adjustable engagement %

Material recommendations

See also: Tap Drill Chart →

🧵

Thread Depth Calculator

Calculate minimum thread engagement for tapped holes. Based on Machinery's Handbook standards for bolt/hole material pairs and safety factors.

UNC, UNF, Metric threads
Material strength ratios
Application type presets
Visual engagement diagram

GEOMETRY & TRIGONOMETRY

📐PRO

Right Triangle Calculator

Solve right triangles from any two known values. Live visual diagram with hover tooltips shows all dimensions.

Solves from any 2 inputs
Imperial/Metric toggle
Decimal & DMS angles
Interactive SVG diagram

📐

Sine-Bar Calculator

Calculate angle/height relationships for sine bar setups. Used for precision angle measurement in layout tables and milling vises.

Solve for angle or height
Inches/millimeters toggle
Decimal & DMS angles
Visual sine bar diagram

⌒

Chord Length Calculator

Calculate circle segment and chord relationships for keyways, circular features, and arc machining operations.

Solve from R/D + one parameter
Angle, chord, height, arc length
Inches/millimeters toggle
Visual circle segment diagram

MEASUREMENT & CONVERSION

📏

Tolerance Stack-Up Calculator

Worst-case and statistical (RSS) tolerance analysis for assemblies with multiple dimensions.

Worst-case analysis
RSS statistical method
Dynamic dimension list
Visual stack diagram

✨

Surface Finish Converter

Convert between Ra, Rz, RMS, and ISO N-grade surface finish specifications.

Ra, Rz, RMS, N-grade
Microinch/micrometer units
ISO 1302 standards
Surface profile diagram

REFERENCE & LEARNING

📖

G-Code & M-Code Reference

Complete searchable reference for G-codes and M-codes. Includes usage examples, notes, and machine compatibility.

50+ G-codes and M-codes
Search and filter functionality
Mill and lathe compatibility
Usage examples for each code

📚

CNC Programming Basics

Complete beginner's guide to CNC programming. Learn G-code, M-code, coordinate systems, and program structure.

Coordinate systems explained
Canned cycles for drilling
Complete program examples
Safety and best practices