Millimeter - screen ruler app

In-app purchases
1.73K reviews
Content rating
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image

About this app

Millimeter is a simple free screen ruler app. You can measure small objects that fit the device screen with this ruler. There are NO ADs in the app for the best experience and real full-screen measurements.

โ˜› ANY DEVICE can be calibrated for accurate measurements in Calibration Mode, where common standard objects (coins, credit cards, etc) can be used as a reference.

You can also customize your app by purchasing extra features or modes.

๐Ÿ“ What you can do in the free version of the on-screen ruler:

- Calibrate Millimeter with custom or standard objects
- Ruler Mode for the measure in metric and imperial units: mm and inch
- Additional vertical ruler for 2D measurements (๐Ÿ“)
- Area measurement for 2D measurements (โฌ›)
- Calculate W/H ratio of the rectangular objects in 2D
- Lock / Unlock rulers in any mode for better usability (๐Ÿ”’)
- Fine grid (1mm for millimeter units) ๐Ÿ‘
- Use fractions for inch units
- Read interactive Help / Guide about all available features in a mode
- Use the app as a standard ruler
- Use full-screen mode for better user experience in Ruler mode

๐Ÿ’ณ You can customize your free version and purchase extra modules and features that add the following functionality:

- Spirit / bubble level for checking incline or tilt angle ๐Ÿ”ฎ
- Parts Mode to split length or objects in equal parts
- Thread per inch ( TPI ) measurement pattern (๐Ÿ”ฉ) in Parts mode (
- Circle Mode to measure circular objects (๐Ÿ”ด)
- Split circle into equal sector / angle
- Protractor / Goniometer Mode - measure angles (โšช)
- Set exact size, length, diameter, number of parts manually with keyboard input (โŒจ)
- Change background to BW night mode for power saving (๐Ÿ”‹) and better visualization (๐ŸŒ“)

Use this screen ruler in different areas to measure small objects that fit your phone or tablet screen: jewelry, jewels, rings ๐Ÿ’ , stones, screws, bolts, buttons diameter, nuts, knitting needles, knitting pattern, washers, insects, mosaic tile, hooks, thread, frame wrap angle, etc.

Units: millimeter (mm), inch (in). Fractions are supported for inch units.

Supported languages:
- English, German, Russian, Japanese, and French languages.

๐Ÿ“– More about the app:

โ˜Ž If you have any problems with the app on your device, please contact first and we will help you. Thank you.

VisTech.Projects Team.
Updated on
May 3, 2023

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
Learn more about how developers declare sharing
This app may collect these data types
Location and App activity
Data is encrypted in transit
Data canโ€™t be deleted

Ratings and reviews

1.62K reviews
jessica siu
February 25, 2023
I used an 8mm earring for measurement and it's really accurate. Even with default calibration it shows what it has to show. With the size of a credit card for calibration it comes as a handy tool too if the default falls short, so it's a well done indeed. So now I can at least have an idea when I online shop how big an object is.
7 people found this review helpful
Did you find this helpful?
February 25, 2023
Jessica, thank you so much for taking the time and share your experience with our app! Glad you found it handy and helpful for your online purchases. You are absolutely right, default calibration works on some devices but any known size object can be used for calibration, so the app should work accurately on any device after calibration.
Richard Bowerbank
June 13, 2020
What a super little app for positioning tables, diagrams, pictures, etc in documents, pdfs. Best using it as a pop-up app overlaying say an Adobe document, as it can be faded (made see through), and it is easy to go back and forth. Just brilliant. And feedback!
65 people found this review helpful
Did you find this helpful?
June 13, 2020
Thank you very much for your feedback! Contact us at if you have feature ideas for the purpose you are using the app, we will be glad to hear from you and maybe implementing if it fits the app. Thank you for your support!
A Google user
May 5, 2019
UPDATED REVIEW: When I 1st installed this app, I tried calibrating w/a CC. I couldn't get it 2 work, since I was unable 2 use my keyboard. Maybe it was operator error, OR maybe there ought 2 B better instructions 4 calibrating this way. After getting my screen size 4 my Galaxy S9, (FYI it's 146.5mm, 14.65cm or 5.8 in, 4 those who need it) I chose the 3rd option 4 calibrating w/my screen size. WOO-HOO! It worked! So apparently it was operator error. I revoke my 1 star & give u 5 star's! Thanks!
37 people found this review helpful
Did you find this helpful?
May 6, 2019
Maria, Thank you very much for taking time to update your review with details and for supporting the app! ๐Ÿ‘ VisTech.Projects Team.

What's new

v2.3.3 - fixes and improvements for new versions of Android
v2.3 New features:
- fixes and improvements
- new Level feature (paid) available in Pro version

v2.2 New features:
- Fine grid
- lock screen
- 2D ruler
- multi touch support (for easy measurements when object touches screen)
- fixes and improvements

v2.1 - new Protractor Mode( in-app purchase or in Pro version) for angle measurements: