Accuracy 2 mechanical watches accuracy measuring tool
Accuracy 2 mechanical watch accuracy measuring device
Accuracy 2 mechanical watch accuracy measuring device from the top
Accuracy 2 mechanical watch accuracy measuring device from above
The ONEOF® Accuracy Pro, high-end multi-position acoustic sensor for the measurement of mechanical watches

Accuracy 2 - Acoustic Measurement Device

The ONEOF Accuracy2 is a compact and powerful acoustic measurement device for testing the accuacy of your mechanical watch.


The ONEOF Accuracy2 uses an ultra sensitive sensor which is capable of detecting every single vibration in the movement of a mechanical watch. Each of these small vibrations is converted into an audio signal and then highly amplified, digitalized and transmitted to the mobile app. In the app, the data is gathered, analysed and interpreted through an easy-to-read graphical interface.

  • Sensitive piezoelectric sensor
  • High precision temperature compensated quartz oscillator
  • +/- 0.5 s/d accuracy
  • Dark grey anodised unibody aluminium Casing
  • Soft touch pad
  • Dimensions : 40 x 40 x 8mm
  • USB-C connector, cable and adapters included
  • Wordwide shipping
  • All orders shipped from Switzerland

One Step Ahead, Once Again

While other connected measurement tools on the market work only with the analog and disappearing audio jack connector, ONEOF engineers developed a brand new digital audio electronic system based on the commonly used USB standard.

No jack connector

The jack connector with analog audio is outdated. The 16 bits / 48KHz digital audio used in ONEOF Accuracy2 gives better measurement performance than any other product available on the market.

Plug and Play

The ONEOF accuracy2 is a stand-alone device. It requires no battery or power supply. Plug it in and forget it, it is that simple.

Download Software

iOS & Windows

The new Accuracy app developed by our engineers automatically detects the presence of your watch on the sensor. Just after a few seconds of initialization, you get all the detailed technical information you need in a professional and user-friendly app.

How accurate is your timepiece?

HYT Chronograph Watch

swiss logo

All H2i products are designed, manufactured and assembled in Neuchâtel, Switzerland. We have always taken special care to provide both high performance and user-friendly interfaces. All our software is developed in-house with the latest native programming languages.



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