Inches ⇄ mmPlans + cut listsShop friendly

Metric Converter Calculator

Jump between imperial and metric without the mental gymnastics. Great for imported plans, CNC/laser dimensions, hardware specs, and “why is this part 18.3mm?” moments.

Fast workflow
  1. Choose what you’re converting (length, area, etc. if supported).
  2. Enter the number once.
  3. Copy the result directly into your cut list or CAD note.
  4. Round intentionally (hardware tolerances matter).
Tip: For joinery, round to the tool you’ll actually use (tape, calipers, CNC, etc.).

Metric Converter

Converts length units bidirectionally using precise base factors.

How to use

  1. Enter your measurement in the source unit.
  2. Read the converted value instantly.
  3. Round based on process (tape vs calipers vs CNC).
  4. Save your conversion if you’re repeating the same dimension a lot.

Pro tips

  • • CNC/laser: keep decimals, don’t “helpfully” round them away.
  • • Tape measure work: round to the closest practical fraction or mm mark.
  • • Hardware: check spec sheets (bolt sizes are not always “nice” conversions).

FAQs

Should I round up or down?

Round based on fit. For clearance, round up a hair. For tight joinery, stay exact or test-fit with scrap.

Why do metric plans look “weird” in inches?

Because they’re exact in mm, not in fractions. Converting can produce odd decimals. Keep the source system whenever possible for fewer compounding errors.

© 2026 WoodWorkCalc · helping makers build profitable, sustainable businesses.

© 2026 WoodWorkCalc

© 2026 WoodWorkCalc — Helping woodworkers build profitable, sustainable businesses.

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