Engineering Tools

Mechanical engineering tools for faster review work

Practical calculators and references for engineers working through drawings, screenshots, specifications, and review packets.

GD&T references

GD&T Tools

Reference-only GD&T tools for approximating tolerance zones, position with MMC/LMC bonus examples, profile, perpendicularity, and related drawing review concepts.

Start with the plus-minus tolerance approximation converter. It is for reference only and is not exactly correct.

Unit converter

Mechanical Engineering Unit Converter

Convert common mechanical engineering units for length, force, mass, stress, temperature, power, and torque.

Includes mm to inches, lbf to N and kgf, GPa to ksi, deg C to deg F, W to BTU/hr, N*m to lbf*in, and more.

Fits and limits

ISO Fits Calculator

Estimate hole and shaft limits, minimum clearance, maximum clearance, and fit type for ISO-style mechanical fits such as H7/g6.

Reference-only approximation for common fits including H7/g6, H7/h6, H7/f7, H7/k6, and H7/p6.

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