NH35 vs NH36: a source-backed specification comparison
Compare the NH35A and NH36A using current TMI documents: calendar, frequency, running time, dimensions and stated accuracy range.
Last fact-checked:
The documented difference between the NH35A and NH36A is smaller than many online comparisons suggest. The NH35A displays the date. The NH36A displays the day and date. Time Module (TMI) lists the same main dimensions and performance specifications for both.
Sources last checked on 30 July 2026. This article compares published manufacturer data. It is not an in-house laboratory test. TMI states that specifications may change without notice.
Short answer
- NH35A: three hands, date and quick date correction.
- NH36A: three hands, day plus date and quick day/date correction.
- Both: automatic and manual winding, stop-second mechanism, 21,600 vibrations per hour (3 Hz), 24 jewels and more than 41 hours of running time when fully wound, according to TMI.
The practical choice is therefore not which calibre is universally "better". It is which calendar display the dial and the complete build require.
Manufacturer specifications compared
| Field | NH35A | NH36A |
|---|---|---|
| Display | 3 hands + date | 3 hands + day and date |
| Automatic winding | Yes, ball bearing | Yes, ball bearing |
| Manual winding | Yes | Yes |
| Stop-second mechanism | Yes | Yes |
| Quick correction | Date | Day and date |
| Frequency | 21,600 vph (3 Hz) | 21,600 vph (3 Hz) |
| Jewels | 24 | 24 |
| Running time | More than 41 hours | More than 41 hours |
| Stated static accuracy | -20 to +40 seconds/day | -20 to +40 seconds/day |
| Outside diameter | 27.40 mm | 27.40 mm |
| Casing diameter with dial holding spacer | 29.36 mm | 29.36 mm |
| Total height | 5.32 mm | 5.32 mm |
TMI's accuracy range applies under its stated measurement conditions. It is not a promise for every assembled watch and does not describe a particular regulated movement.
What the calendar difference means
On the NH35A, the first crown click adjusts the date. On the NH36A, turning the crown in one direction adjusts the date and turning it in the other adjusts the day. TMI warns not to set the date on either the NH35A or NH36A between 9 p.m. and 4 a.m. The cited wording concerns date correction and does not support a blanket claim about day-wheel correction.
For a build, this means:
- The dial needs the appropriate calendar opening.
- Movement, dial, hands, holder, case and crown position must be checked as one system.
- Matching outside dimensions alone do not prove that two specific part combinations are interchangeable without further checks.
An NH36A may sit behind a dial that hides the day display, but the extra function then provides no visible benefit. An NH35A cannot display a day of the week.
What the documents do not establish
The cited TMI material does not establish a universal retail price difference, guaranteed performance after regulation or which calibre is more common at repair shops. Those claims depend on supplier, batch, assembly, regulation and measurement conditions. We do not publish a number without a documented first-party data set.
The calibre name alone also does not establish the origin of a particular unit. TMI lists Japan or Malaysia for the NH35/NH36 line. The marking on the actual movement is what matters.
Sources and open data
- TMI NH0/NH3 product line
- TMI Technical Guide for NH34A to NH39A, 2025 version
- TMI NH35A specification sheet
- TMI NH36A specification sheet
- Download the machine-readable comparison as CSV
The CSV contains only fields traceable to the linked TMI material, including source URL and verification date. It does not replace a compatibility check for a specific watch build.
For more context, see our NH35 movement overview. If you do not want to combine components yourself, the configurator shows the available options.
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