Miyota Caliber 1m12 Plastic Movement Holder

Miyota Caliber 1M12

Miyota Caliber 1m12 Plastic Movement Holder

Manufacturer Miyota (Citizen)
Caliber Number 1M12
Type Quartz
Replacement Caliber
Lignes 10.5”’
23.7mm x 22.6mm
2.71mm thick
Battery Cell Number 363 / 364 (SR621SW)
Battery Life
~3 years
Jewel Count
Frequency 32,768Hz
Quartz Type Tuning fork type quartz crystal
Stem 065-505 (tap 10)
Hand Sizes 1.20mm / .70mm / .17mm
Driving System Two-pole stepping motor
Hacking Seconds?
Hand Count
Functions Central hours; central minutes; central seconds; date calendar at 3:00
Country of Manufacture Japan
Known Models Android Mantis (Add your watch to the comments below…)

The Miyota caliber 1M12 is part of the 1L/1M family of affordable quartz calibers. The 1M12 is a 0 jewel quartz movement that is made in Japan. Although you can still find this caliber for sale, it has since been replaced by the Miyota caliber GM10 or GM12.

1M12 VS 1M02:

Miyota makes a similar caliber 1M02. The main difference when comparing the two is that the 1M02 also has a bilingual day of the week complication. Therefore, the 1M12 is a date movement and the 1M02 is a day-date movement.

1M12 VS 1L12:

There is a 1L12 that is basically the same as the 1M12, except that it is smaller in size. The 1L12 is 15.3mm x 18.2mm compared to the 1M12 at 23.7mm x 22.6mm.

1M12 Accuracy Rating:

Miyota states the accuracy of this movement to be +/-20 seconds/month when “worn under normal circumstance”.

Battery Cell:

The cal. 1M12 takes an SR621SW (364) watch battery. The battery is said to last up to 3 years. There is a battery saving (aka hacking) mode by pulling out the stem into time setting mode (position II). When doing this, the seconds hand will stop and the power consumption will be limited. Below is a view of the empty battery tray. No insulator film is necessary since the base is plastic.

Miyota Caliber 1m12 Battery Tray

Replacement Price:

At the time of this post the replacement price of a new Miyota calibre 1M12 is around $7 – $9.50 USD.


The good thing about the small, cheap Miyota movements is that they can usually be interchanged with similar calibers (eg: Miyota 20XX / 21XX / 6LXX / 6MXX) if you can’t find a replacement, or if you want to add or remove additional features to modify an existing watch.

Examples of watches with this movement:

The movement pictured below was found in this Android Mantis model AD499, as shown below with the black plastic movement holder removed from the case. For this watch, Android opted to remove the seconds hands, making it a 2-hander with a date.

Miyota Caliber 1m12


Additional Resources:

Caliber Corner is the world's most popular resource for watch movement pics, specs, mods and DIY repairs. Be sure to check out the member's forum and follow @calibercorner on Twitter, Instagram and YouTube (NOT Facebook). Join our mission to spread movement awareness! Login/Sign-up

Community Reviews & Questions:

  • Keep comments respectful and follow our community guidelines.
  • Keep comments on the topic of Miyota Caliber 1M12

For off topic or general watch questions, post in the Caliber Corner Forum.


newest most voted
Inline Feedbacks
View all comments
1 year ago

Also in Skagen Titnium 233XLTTN

2 days ago
Reply to  Jim

I have it. Buying a replacement movement now. Its a nice watch.

11 months ago

I too have this in a Skagen Titnium 233XLTMO

I have just opened the watch myself rather than a jeweler, so as to change the battery, since it had stopped working (in a draw for a couple of years!).
I have found that the spacer ring is in three pieces and there is no seal rubber ring (shan’t trust jewelers again).
Now the question is – can I get a spacer ring and a rubber ring from you for this exact model?

7 months ago

In my Casio Oceanus watch with Miyota 1M12 movement is the battery life unfortunately ONLY 3 months. I have tried with different batteries, but the result is still the same. Any suggestions are welcome.

5 months ago

Also Festina F16374 features this movement.

4 months ago

Skagen SKW6025 (NOT waterproof, because seal was unuseable at first battery change, otherwise rated at 3ATM for hand-washing) This 1M12 is my ONLY surviving Citizen/Miyota caliber, with Seiko/TMI/Hattori outliving everything else! In my little collection of 20+ watches, THIS is my most accurate caliber, with so far gaining about 1.5 seconds in almost 2 months, since I set all watches and replaced most batteries with dirt cheap “Beidongli” SR621SW 15cent batteries from Amazon. Those are actually well rated batteries! Second most accurate is an Invicta Pro Diver with Seiko/TMI/Hattori PC32A, gaining 3 to 4 secs/month. The only thing better is… Read more »

Seagull Caliber St19

Join our mission to spread movement awareness!

Members Online

  • admin keepthetime FriendlyGooner farrukh2102

Recent Forum Posts

Trending Comments

Hans Groenewegen

Orient Caliber F6922

I've had my Mako and Ray Orient watches with these calibers, I guess. Their performance…


Sellita Movement Grades

Yes. The diameter and height will be the same. The main differences are the finishing,…


Sellita Movement Grades

Can they be exchanged ie upgraded? Same dimensions?


Rolex Paraflex

ROLEX 3136


Raymond Weil Caliber RW4251

I have the watch on hand and can confirm the RW4251 is based on the…


Would love your thoughts, please comment.x