Measure and track the accuracy of your mechanical watches. Toolwatch is a free watch accuracy app trusted by the watchmaking industry's leaders and 15 000+ monthly users. Is your watch accurate? Should it be serviced? How does it compare versus other watches? Find out now by measuring the accuracy of your watch!

Toolwatch also brings to you the best tips, tailored on your watch for taking care of your watches.

"Toolwatch is the best watch accuracy app out there and it's free!" - Guillaume Cassez, Manufacture Jaeger-LeCoultre

"I regularly check the accuracy of my watch collection and Toolwatch is my favorite app for that." - Thomas Hulin, Van Cleef & Arpels

"I had the feeling my watch was running late, now I am sure thanks to Toolwatch and I could get my watch serviced for free as it was still under warranty!" - Benjamin Baudisson, Vacheron Constantin

"As a watch collector, knowing when to service my watch is crucial. Toolwatch helps me taking care of my mechanical watches." - Alex Ghotbi, Watch Specialist- Associate Director at Phillips Watches

As seen on ABlogToWatch, FratelloWatches, Theo & Harris, WristReview, Europa Star and more.

Find out now if your watch is accurate, it is FREE using Toolwatch mobile app.

What’s New

Version 1.3.12

In this version, we focused on bug fixes. In details:

- Watches with more than 1 and less than 2 measures were not properly displayed;
- The autocompletion on calibres wasn't available;
- Errors messages weren't displayed properly;
- Wrong password on login was crashing the app.

Ratings and Reviews

2.9 out of 5
95 Ratings
95 Ratings
Antmar7 ,

Doesnt seem accurate

Im not sure if Im just not using this app correctly or if its just not accurate. I have a COSC certified watch and its typically about +4 seconds per day. The first couple of measurements looked ok with a +5 s/d and +7 s/d deviation. I assumed the deviation was due to being worn if a more rough environment. However, after sever other measurements were taken over two weeks, the readings ranged from -29s/d to +77 s/d which is outrageous considering the actual deviation appeared to be significanly less. The app then told me to get my watch serviced. I decided to compare the time to the national atomic clock, and according to that, my watch is approx +2 s/d. So either Im doing something wrong or the app is wrong. Im gonna lean towards the latter. Also, having to make an account is really stupid. I’ll give it another couple of chances to see if it stabilizes or I’ll delete it.

spirtnoye ,

Simple to use with minimal complaint!

This is a great app for timing your watches. It's simple, clean, and very easy to use. My ONLY complaint is that I cannot seem to edit the info of my watches once I've added a watch to the list of those I've timed. So, make sure you get it right the first time if you don't want to go on adding a watch multiple times. Other than that, it's my go-to for fast, simple, and accurate measurement of my timepieces. Definitely recommend this app if you're looking to see how well your watches are performing.

Baroosk ,

Clumsy and limiting

I use because there’s not much else for iphone. Why does it require 12 hrs between measures? What if i wanna check at noon then 10pm? I was a Watchcheck user and that was a much better app. I wanna see the time as i set it. I wanna see a setting for how I left the watch (flat, worn, on winder, 3 o’clock up, etc). I wanna see a list of the times, not an average mysteriously calculated behind the scenes. Again Watchcheck had these.
I will admit it shows if a watch is off, but it leaves the process a mystery, behind the scenes. Please assume some intelligence in your users please. This app could do a lot but it is very dumbed down and Leaves me qeustioning it.


Mathieu Nayrolles
14.2 MB
Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.
Age Rating
Rated 4+
© 2016 Inc


  • Family Sharing

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

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