Measure anything your iPhone or iPad can take a picture of!

★★★ 40% off the full version of RulerPhone, right now! Celebrating with a sale! ★★★

RulerPhone has now been downloaded by *many hundreds of thousands* of iPhone, iPad, and iPod users!

“ of the coolest apps I have seen so far.”

“...the best ruler app for the iPhone.”
- iPhoneCave

RulerPhone measures anything your iPhone can take a picture of.

RulerPhone turns your iPhone and its camera into a true measuring tape -- all you need is something already in your wallet: a gift card, MetroCard, driver's license, or credit card.

New Version! RulerPhone can now also measure the distance from your iPhone's camera to any object and save any measurements to your photo library!

Note: RulerPhone Lite allows measurements up to 1.5 feet. To accurately measure anything from a few inches to beyond 12 feet, buy the full version of RulerPhone.

RulerPhone is not like other apps: it does not just display an image of a ruler on your iPhone, and it does not use GPS to calculate distance. RulerPhone can accurately measure distances ranging from a few inches to 10 feet and beyond.

What others are saying:

" of the best applications for the iPhone."
"I was surprised how well this worked...I would buy this for $10."
"Works like a charm...super easy to use."

How does it work?

Place any credit-card sized card next to the object you'd like to measure, snap a picture with your iPhone's camera, align your image with the card placeholder that RulerPhone displays on-screen, and you are ready to measure anything in your picture just by dragging your finger. You can also use any picture already stored in your iPhone or iPod Touch photo library.

RulerPhone figures out the dimensions you're measuring using the card in your picture as reference. Once you've aligned the card in your image with the on-screen card placeholder, you simply drag your finger across the screen to measure distance. RulerPhone will display a ruler over your picture that you can drag and adjust to fine-tune your measurements (as seen in the screenshot below).

Is it accurate?

RulerPhone is accurate within half an inch when measuring distances of three feet or less and can be accurate within a single inch when measuring distances up to 10 feet as long as the instructions are followed closely. Much of RulerPhone's accuracy depends on the user's ability to follow the on-screen instructions and tips for accuracy. Once these steps are mastered, RulerPhone is a very accurate tool. RulerPhone's accuracy will also continue to increase as the iPhone's camera is upgraded.

When does it not work?

RulerPhone does not measure depth in a photograph. When you take a picture, RulerPhone can only measure an object's height and/or width. Similarly, if you take a picture with your MetroCard or driver's license off at an angle instead of pointing directly at the camera, RulerPhone's accuracy will be compromised. All of this information is in RulerPhone's instructions and accuracy tips that are available once you buy the app, and more information is found at the website below.

How can I learn more?

Go to to learn more, get tips, and watch video of RulerPhone in action.

What’s New

Version 4.52

* Quite a few crash fixes -- sorry to those who've run into trouble!

Recent updates:
* Support for iPhone 5's juicy new screen.
* Fix screenshot quality when saving measurements on retina display.
* Crash fixes

Ratings and Reviews

2.0 out of 5
52 Ratings

52 Ratings

Nariosan ,

Promising but disappointing.

Promising interface/premise.
To measure:
1. You put a credit card sized object next to or on top of the object you want to measure.
2. Take a photo w app.
3. Line up/overlay a blue color card sized template over the card.
4. Take a reading.
For me it was useless as it only lets you measure up to 1.5 feet ( 18 inches / 45 cm). For anything else you must pay $$$

I did go ahead and took 3 measurements under 1.5 ft. Sadly it was off in all 3 tries. And by quite a margin! (severely underestimating the real distance).

There seem to be no app for measuring that doesn't ask for more money after saying it's free. Seems like a great premise for a decent developer to come up with a real app. Specially an app that is also accurate.

LaPalma ,

Works for me

It is really up to the user to follow directions. This does what it says it does and nothing more. It does require some skill on behalf of the user. It you have difficulty with a tape measure, you may have difficulty with this tool

Bullseye0 ,

Doesn't let you measure over 1.5' unless unlocked

You must spend money to actually try this product out on large objects. Since I wanted it to measure trees in a landscape project and I wanted to check its accuracy BEFORE spending money it was a waste of my time. It would be better if you let people measure 5 things and disable it. As it is, it is now deleted and you'll never see any cash from me. 0 stars.

App Privacy

The developer, Ben Kamens, has not provided details about its privacy practices and handling of data to Apple.

No Details Provided

The developer will be required to provide privacy details when they submit their next app update.


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

You May Also Like