ClockMaster - Time Regulator 4+

Pendulum Clock Time Regulation


    • 3.7 • 49 Ratings
    • $49.99
    • Offers In-App Purchases

iPhone Screenshots


>>> Check out the demo videos at

ClockMaster is a clock timing software, in many ways similar to watch timegraphers, but specifically designed to work with mechanical pendulum clocks. The app analyzes the ticking sound of the escapement to determine the clock's running rate measured in Beats Per Hour (B/H). This rate is then compared to a specified Target Rate, and the Error is reported as Seconds Per Day fast or slow (±S/D).

The speed of a mechanical pendulum clock is not constant, fluctuating with age and wear, spring tension and even temperature. The ClockMaster app was created with a focus on accurate long-term measurements where traditional timers often do not function very well.

For the professional horologist or interested amateur, you can now test in the field — put the clock in exact beat and regulate the clock with just a few hours of testing. For increased rate accuracy and in depth investigation of clock movement's behavior, you can conduct long-term measurements for up to two weeks (ClockMaster Pro). Branded, printable PDF reports can be generated for each measurement, and the raw data exported as .csv file for graphing in a spreadsheet (ClockMaster Pro).

ClockMaster Pro (in-app upgrade) provides these additional features:

• Save and share branded, printable PDF reports for each measurement
• Export raw measurement data as a .csv file for spreadsheet analysis
• Conduct long-term measurements of up to two weeks

What’s New

Version 3.0.23

Thanks for using ClockMaster! Please rate the app and leave a review!

- This update brings additions to the beat rate database.

Ratings and Reviews

3.7 out of 5
49 Ratings

49 Ratings

Dsmith469 ,

Almost perfect

This app helped me resetting a grandfather clock I had to disassemble and clean & oil. The iPhone ear buds work far better than the internal Mic which is almost useless. A clip-on piezoelectric pickup would be much better still.

They only thing I don't like is that only an absolute delta is shown. It works be most helpful if there was some indication of which half of the cycle was longer/shorter when adjusting the balance. I ended up using a flashing metronome to tell me whether I had to tighten or loosen the pendulum leader offset. Lose one star for this deficiency.

I've tried a couple other apps but this is spot on. I would highly recommend.

Hankk ,

Simple but does the job

I used this to calibrate my cuckoo clock. It picked up the pendulum clicks just fine using the internal mic, with no need for an external mic or sensor. I'm definitely no horologist, but this seemed to do the job. When I had a problem due to an iOS version issue, the developer responded within a few minutes and had a fix quickly.

It would be nice to have plots to look at drift rate and periodic error. These are available in the Pro version, but even in that it will not make plots - just allow you to export the data to a file to be viewed elsewhere. Would be better to have the plots right in the app.

Natemeins ,

Very useful! Works as advertised

This has become my go-to app when I'm fine tuning a clock, whether it be a perfect tick-tock or getting it timed to as little gain/loss per day. It has been frustrating in the past as the app didn't support my iPhone 5-5S, I had to resort to an old 4 for it to work. Just tried it on my 6S+ and had no problems!
I haven't upgraded to pro yet but I am interested as I have a piezo microphone with a 3.5" jack and instead of using my small amp next to my phone I'd love to be able to plug it into my phone and reduce the background noise. $20 is hard to swallow though. Now if it were say $5...

App Privacy

The developer, ONYX Apps, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


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