Comparison

Super Ruler vs Kaliper

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Super Ruler

Features
Read full description

Now you can Measure everything with beautiful on-screen ruler. A simple, user-friendly and accurate ruler for your phone -Caliper mode - Pick your units: mm, cm, inches, m, inch, foot, and yards - Control ruler length as you want, even you can put 100 meter if you want - no calibration needed - Copy current length to clipboard and paste it in another app - Save your current measurement screen as image - Very simple so everyone can use it

About

Kaliper

Measure key cuts accurately using your device's camera. This utility helps decode keys when a physical caliper is unavailable or difficult to read. Offers predefined systems and custom measurement options for various lock types.

Highlights
  • Measure key cuts with device camera
  • Predefined lock systems
  • Custom key measurement input
  • Ad-free upgrade option
  • Supports various lock brands
Features
Read full description

Out-of-the-shop and out-of-the-van key gauge utility. Have a key you need to decode but no caliper or key gauge nearby? Not 100% confident on your eyesight to read the cuts? Then use your iDevice to measure the key with Kaliper. Kaliper is free to download with a purchase option for upgrading. It is recommended to get accustomed to the app prior to purchasing as with any tool, this app has a learning curve and with practice comes perfection. The free version comes with two predefined systems: Arrow .014" and Schlage .015" (5 pin only). The full version comes with eight predefined systems: Arrow .014" (5/6 pin), Best A2, A3, A4 (6/7 pin), Kwikset .023" (standard/titan), Sargent .020" (5/6 pin), Schlage .015" (5/6 pin), and Yale .019" (5/6 pin). In addition to custom key measurements and of course no ads. Instructions: On the main page begin by selecting your iDevice from the choices on the left, then select either a predefined system or custom. Do not use full screen on iPads. 

Predefined: 

Lay your device on a flat surface and place your key on top of the silhouette, using the top shoulder (or bottom tip for best systems) as the primary focus for alignment. If aligned properly each of the cut markers will sit directly above each corresponding cut. If necessary, use the zoom control at the bottom for a better fit. Once the key is aligned, tap on the first down arrow in the upper right hand corner to lower the cut marker. Each tap represents a deeper cut with the depth displayed directly above the arrow. Keep tapping until the marker outlines the cut. If the marker starts to disappear behind the key use the up arrow to raise the marker. Do this for the remaining cuts to finish measuring your key. Custom: The measuring process remains the same as the predefined systems, but as the markers are customizable some measurements need to be supplied before proceeding: Bow to First Cut: The distance from the center of the first cut to the top shoulder. Cut to Cut: The distance between the center of each cut. Shallowest Depth: The distance from the bottom of the blade to the center of the lowest cut in the system (i.e. Zero or One). Depth Increment: The distance between subsequent cuts. These measurements are typically found on pinning kits, however the system you are inputting may be found on the Charts page. From this chart simply tap on the system and all the measurements will be automatically applied. If inputting manually, type the measurements into the 4 boxes and tap Apply. The markers will adjust accordingly and you can begin measuring the key using the shoulder and blade for alignment. If the system uses a One as the shallowest cut, tap on 0 - 9 to reflect a 1 thru 10 cut system. Tap again to switch back. Compatibility (sorted by screen size): iPhone SE2, SE3, 12 mini, 13 mini, 11 Pro, 11, 12, 12 Pro, 13, 13 Pro, 14, 14 Pro, 15, 15 Pro, 16, 16e, 17e, 16 Pro, 17, 17 Pro, Air, 11 Pro Max, 12 Pro Max, 13 Pro Max, 14 Plus, 14 Pro Max, 15 Plus, 15 Pro Max, 16 Plus, 16 Pro Max, 17 Pro Max Found a bug? Something not working? Have a suggestion? Feel free to contact me via email: farren@phoxlocks.com

Screenshots

Super Ruler4 screens
Kaliper4 screens

Verdict

The call

The clearest difference is in-app purchases: Super Ruler at none against Kaliper's 1. Super Ruler also leads on iOS requirement (11.0 vs 14.0). Kaliper's advantage is update cadence (every 8 months vs every 109 months). On price, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Kaliper sells 1 one-off in-app purchase. Super Ruler asks for nothing beyond the download.

UpkeepUpdate frequency

Super Ruler ships an update every 109 months, Kaliper every 8 months. The most recent releases landed on September 15, 2026 and August 25, 2026 respectively.

Scorecard3 real differences · 7 level
Super Ruler versus Kaliper: the parameters behind the verdict, then further details
ParameterSuper RulerKaliper
PriceFreeFree
Rating—4.6 (8 ratings) — better
Positive reviews—50.0% of reviews
Number of ratings—8 — better
Update frequencyEvery 109 monthsEvery 8 months — better
AdsYesYes
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS11.0 — better14.0
Further details — not scored
Size8 MB4 MB
Age rating4+4+
DeveloperHany ElmehyFarren Domenici

In-app purchases

None

Super Ruler

No in-app purchases

1 purchases

Kaliper

One-time1
  • Kaliper Full Version$1.99

Questions

Is Super Ruler free?
Super Ruler is free to download, with no in-app purchases.
Is Kaliper free?
Kaliper is free to download, with in-app purchases available.
Do Super Ruler or Kaliper have ads?
Both Super Ruler and Kaliper show ads.
Which is updated more often, Super Ruler or Kaliper?
Super Ruler ships an update every 109 months, and Kaliper every 8 months. Most recently, Super Ruler was updated on September 15, 2026 and Kaliper on August 25, 2026.

Other comparisons