Free engineering calculators.
33 interactive calculators for QA, design, and production engineers. No signup. No paywall. Built and tested by working engineers.
Tolerance Stack-Up
Worst-case + RSS analysis. Multi-dim assembly stack.
→AS9102 Form 3 Builder
Paste dims → editable Form 3 → PDF export.
→Cp / Cpk / Pp / Ppk Calculator
Process capability + histogram from sample data.
→PPAP Submission Checklist
Level 1–5 status tracker, 18 elements.
→Cost of Poor Quality (COPQ)
Rejection rate → ₹ wasted per month.
→Position Tolerance & MMC/LMC Bonus
True position + bonus tolerance from feature size deviation.
→GD&T Symbol Reference
14 ASME Y14.5 symbols, worked examples.
→ISO 286 Fits & Tolerances
H7/g6, H8/h7, hole-basis & shaft-basis.
→Surface Finish Converter
Ra ↔ Rz ↔ Rt ↔ µin/µm ↔ N-grade.
→Gauge R&R (MSA Type 1)
Cg / Cgk capability study from repeated readings.
→AQL Sampling Plan
ANSI Z1.4 / ISO 2859 — sample size, accept/reject.
→FMEA Risk Priority (RPN)
Severity × Occurrence × Detection + AIAG-VDA AP.
→Six Sigma DPMO / Sigma Level
Defects per million ↔ sigma ↔ yield.
→Hardness Conversion
HRC ↔ HRB ↔ HV ↔ HB ↔ tensile (ASTM E140).
→Drill Size Chart
Tap drill, clearance hole. Metric, fractional, number, letter.
→Material Weight Calculator
Plate, bar, pipe, ring weight from 60+ materials.
→Bolt Torque & Preload
VDI 2230 torque from bolt grade, friction, preload target.
→Beam Deflection / Bending
Cantilever, simply-supported, point & UDL loading.
→Press / Interference Fit
Hub stress, push-out force, shrink-fit calc.
→Thread Pitch & Tap Drill
Metric, UNC, UNF, BSPP, NPT.
→Motor HP / Power Calculator
Power ↔ torque ↔ RPM, 3-phase electrical, Indian 415V.
→V-Belt Drive Calculator
Belt length, ratio, belt speed, tensions for A/B/C/D.
→Spur Gear Calculator
Module, DP, pitch & centre distance for any gear pair.
→Pump Power Calculator
Hydraulic kW, motor sizing from flow + head + fluid SG.
→Cycle Time / Cost Estimator
Setup + run + labor + overhead → ₹/part.
→Sheet Metal Bend Allowance
Flat blank, BA, BD, OSSB by material & thickness.
→Machining Speeds & Feeds
RPM, feed, MRR, kW by material + tool.
→OEE Calculator
Availability × Performance × Quality.
→Takt Time & Line Balancing
Takt, cycle gap, line efficiency, required stations.
→Welding Heat Input
kJ/mm for SMAW, GMAW, GTAW, SAW, FCAW.
→EOQ (Economic Order Quantity)
Optimal order size, ROP, safety stock, total cost.
→CadNexa ROI Calculator
Monthly FAI count → ₹ saved + hours saved.
→Engineering Unit Converter
Length, force, pressure, torque, temperature, etc.
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