Best Free Metric Ruler Apps

250+ iOS apps curated and reviewed

4.2 avg rating
19 free apps
Updated October 2026

The best free metric ruler apps on iPhone average 4.2★ across 250+ titles — we've ranked them by what real users actually keep on their phones. Updated October 2026.

Compare top Free Metric Ruler Apps (October 2026)

#AppPriceRatingAdsIn-App PurchasesUpdated
1Rul3rRul3rFree4.4★ (1.1K)YesYesNov 2026
2Ruler®Ruler®Free4.3★ (35K)NoYesNov 2026
3Ruler - CM, MM, InchesRuler - CM, MM, InchesFree3.5★ (79)YesNoNov 2026
4Tape Measure™Tape Measure™Free4.4★ (90K)NoYesNov 2026
5Edge RulerEdge RulerFree—NoYesSep 2026
6Ruler: CM, MM & InchesRuler: CM, MM & InchesFree5.0★ (2)YesYesOct 2026
7Cetvel RulerCetvel RulerFree—NoNoMay 2026
8量尺 Ruler量尺 RulerFree—NoNoOct 2026

Top Picks for Free Metric Ruler

Rul3r#1

Rul3r by YOYASOFT LLC

Ruler, Altimeter and More
Editor's Choice
🔧 Utilities
4.4(1.1K ratings)
FreeAdsIn-App Purchases
Rul3r screenshot 1
Rul3r screenshot 2
Rul3r screenshot 3
Rul3r screenshot 4
Rul3r screenshot 5
Rul3r screenshot 6

This utility app provides a portable ruler for on-the-go measurements. It also includes a suite of additional tools like a protractor, spirit level, and various meters for diverse measurement needs.

Ruler®#2

Ruler® by Tue Nguyen Minh

+ Photo Ruler & AR Measure
Strong Contender
🔧 Utilities
4.3😞(35K ratings)
FreeIn-App Purchases
Ruler® screenshot 1
Ruler® screenshot 2
Ruler® screenshot 3
Ruler® screenshot 4

This app provides a versatile toolkit for all your measurement needs. It includes a classic ruler, a tape measure, and a camera ruler for precise measurements. Easily switch between units and document your findings by adding measurements directly to photos.

What We Love

  • 🚀 Accurate measurements
  • 👍 Easy to use
  • 🔍 Convenient for small items
  • 📏 Useful ruler tool

Room to Improve

  • 💰 Paywall for basic features
  • ⏱️ Limited free usage time
  • 🔍 Inaccurate for larger objects
  • 🙅‍♀️ Aggressive monetization tactics
Ruler - CM, MM, Inches#3

Ruler - CM, MM, Inches by Noadit, Inc.

CM, MM, In. Measure Anything.
Worth Considering
🔧 Utilities
3.5😞(79 ratings)
FreeAds
Ruler - CM, MM, Inches screenshot 1
Ruler - CM, MM, Inches screenshot 2
Ruler - CM, MM, Inches screenshot 3

Measure lengths, widths, and diagonals accurately using your phone. Switch between metric and imperial units, and utilize flexible starting points for precise measurements in any direction. Features auto-calibration for minimal error and a screen lock to preserve readings.

What We Love

  • 👍 Simple and easy to use
  • 📏 Accurate measurements (for some)
  • 💡 Useful for small objects
  • ✨ Clean interface
  • 🚀 Fluid performance
  • 🛠️ Good basic functionality

Room to Improve

  • 😠 Excessive and intrusive ads
  • 🚫 Ads block measurements
  • 🔊 Loud and shocking ads
  • 💸 No option to pay for ad-free (or purchase lost)
  • 📉 Inaccurate inch measurements (decimal vs. fractional)
  • ⚠️ Shady download practices
  • ⚫ Black screen issue
  • 👆 Finger obscures measurements
  • 📱 Inaccurate on specific devices
  • 👎 Lost paid features after update

More Free Metric Ruler apps to explore

FAQ about Free Metric Ruler

What are the best free metric ruler apps for iPhone?
Rul3r tops our free metric ruler apps ranking as of October 2026, with a 4.4-star average from 1.1K App Store ratings, and it's free to download.
Rul3r shows ads and offers in-app purchases, according to its App Store listing as of October 2026.
We track 250+ free metric ruler apps on the iOS App Store as of October 2026, ranked by rating, recency, and analysis of real user reviews.