Tachymeter Explained! (5 examples)

This video aims at clarifying the tachymeter function found on some watches. Hope it helps! :)
Link to my KZbin channel: / erikphotography
Link to my first video review of this watch: • New Omega Speedmaster ...
Link to my second video review of this watch: • Omega Speedmaster Raci...
Text to this video is added below:
A tachymeter (also spelled as "tachymetre") is a function on a watch primarily used for measuring speed; however, it can be used to compute many other things as well.
The tachymeter scale is usually inscribed around the bezel or the outer dial of the watch. Mathematically, the Tachymeter Dial = 3600 divided by the Elapsed Time In Seconds.
As a result and due to accuracy and practical reasons, the printed tachymeter scale is valid for all times up to one minute from approximately 7 seconds.
Moving on to some examples.
Example 1: Let’s say you are watching a racing event and you want to determine the speed of a car. In the race magazine, you read that the distance between Curve A and Curve B is exactly 1km. Using your chronograph, you notice it takes the racecar 20 seconds to cover this distance. The tachymeter scale reads 180. This means that the average speed of the car was 180 kilometers per hour. Keep in mind; you can use other units of measurement. For example,
Example 2: The race magazine also tells you there is a distance of 1 mile between Curve A and Curve C. Repeating the exercise, it takes the car 35 seconds to cover this distance. The tachymeter scale now indicates slightly above 100, meaning the car’s average speed was just above 100 miles per hour.
Example 3: Another example, let’s say we want to measure how fast Usain Bolt runs 200 meters in the Olympics. Using the chronograph, we notice it takes him 20 seconds to complete the race. The tachymeter scale indicates 180 km/h; however, we have to be careful and remember the race was only one fifth of a kilometer, so we need to get one fifth of 180 which equals the actual average speed of the runner; 36 km/per hour.
Example 4: Another example, let’s say you visit a car factory that completes one car every 45 seconds. Reading from the tachymeter, you conclude the factory on average completes 80 cars per hour.
Example 5: Now let’s say you’re visiting a luxury watch manufacturer. Observing the assembly line, you notice the manufacturer produces one watch every 100 seconds. You can still use the tachymeter scale even if this time is above 60 seconds. In other words, if the manufacturer produces one watch every 100 seconds, this is the same as half a watch per 50 seconds. 50 seconds is within the valid range of the tachymeter scale and as a result, you can calculate that 72 half watches (or 36 whole watches) are completed on average in one hour.
If you enjoyed this video, visit my channel to see other explanation videos and watch reviews including a review of this Omega. Have a good day, bye!

[@iannickCZ]

I think no more than 3 people on Earth use this function.

[@angryagain68]

It's also useful to verify your speedometer. I've done that numerous times with my various motorcycles I've had over the years. (Motorcycle speedometers are notoriously inaccurate). Just replacing tires has a huge impact on it's accuracy as well. It's easier for me o just look at my watch than to fiddle with a smart phone will riding.

[@GanNing221]

@@angryagain68 That's one way to get into an incident.

[@angryagain68]

@@GanNing221 Nonsense

[@CapeTownTom]

@@GanNing221 have to agree with you. someone doing all that maths while on two wheel. hopefully he is an organ donor :-P

[@Strellock]

@@CapeTownTom There's really no math at all to do. You can for instance use two physical 1km milestone indicators to be sure of your distance; can even remove your watch from your wrist and hold it in one hand so you always have both hands on your handle bars. Approach the first milestone at speed, you press one pusher, approach the next milestone, press the same pusher again, you never look at the watch at all. All you have to do is glance at your bike's speedometer once between the two milestones to get a reading. Then you pull over safely and everything, and look at your watch. All you do is compare your speedometer's reading, you hopefully still remember :D, with your tachimeter reading. If you're traveling at 60 kph you're gonna take 60 seconds to travel 1 km, so you don't have to ride dangerously either, quite on the contrary, it can be a slow ride. Also, you want to ride at a rather slow speed, because the faster you travel, the harder it is to get an accurate reading on a watch face tachimeter scale; just look at a tachimeter scale, you'll see how it is busier towards in the beggining, aka, the fewer seconds you need to elapse that kilometer, aka, riding like a maniac. ... Remember, people used to use mechanical watches all the time to tell distances, in fact relied on them, heck, soldiers under pressure of losing their lives did it. And better believe it, an uneducated dude under pressure of having their butt shredded was far from some genius mathematician. (And, yes, soldiers used to use telemeter scales, but the reading was the same, if they had the luxury of a stopwatch they didn't even need to look at their watches between the two events) It's a simple reading a tachimetre reading. I guess we assume that it's hard or cumbersome because we never used the technology, never had to, but it was never intended to be hard, on the contrary, it was invented to remove the need for calculation, the need to do the math. It's an instant reading. Many that used tachimeter scales would even learn the scale by heart, could approximate the speed without need for the tachimetric indication on regular stopwatches. And you know, just how you don't need to be reminded of the basic interaction with your smartphone after you get used to it, just as you feel that it's the simplest thing in the world, so does it feel to read a tachimeter to someone who's done it once or twice. And overall using a smartphone is at least one order of magnitude more complicated than reading a watch, but again, we're used to them so we don't perceive it as a challenging interaction.

[@Airborne-80]

Today is July 5th 2024, my 62nd birthday. I received a citizen watch and thought about my large collection of watches. I figured now that I’m old, retired and slowed way down, I might as well finally find out what the hell this tachymeter is used for. Thank you for the awesome explanation. Now….im off to determine some speeds, production numbers, etc.

[@SP-qi8ur]

😂 same here, gift for my 24 birthday

[@NOT-A-BAD-GUY]

All people who had a decent watch for Christmas are watching this video....

[@elduderino1329]

A decent watch doesn't need a nonsense gimmick like a tachymeter on it.

[@zachdurocher1166]

@@elduderino1329 But most watches with chronographs are decent watches *and* usually feature a tachymeter to go along with the chronograph

[@m.l.5067]

@@zachdurocher1166 False : not all fancy watches have a tachymeter, and not all watches with a tachymeter are fancy watches. In fact, they are pretty much watches with shitty and useless functions just to look interesting.

[@sethproaps8899]

Reading this this christmas.

[@thebritishbrick809]

@@sethproaps8899 ye same haha

[@sandeep2435]

I myself teach physics in colleges even though i didn't understood the meaning and how to use the tachymeter on a modern watches but after watching this it is now crystal clear to me .What a explanation .

[@ternsjo]

Thanks, much appreciated. I’m glad I could help.

[@juliansedor7101]

You teach physics but you can't use proper English.

[@preciousjose]

@@juliansedor7101 fun fact: English is one of many languages humans speak in, physics can be taught in any language.

[@rainvast8982]

@@juliansedor7101 you're a perfect example of an American

[@igorchistyakov8876]

@@preciousjose, yeah, but they're all just gibberish mumbling to make tourists comfy with "exotic". He clearly knows the Truth, no need to lie anymore. English is the only language to ever exist.

[@Blue_3rd]

Possibly the second least used function on a watch, after the helium escape valve.

[@tazboy1934]

Helieum escape valve?

[@jamestkirk6000]

Tazboy look at the Rolex Sea-Dweller and Omega Seamaster Professional diver models. ;)

[@scottsteibel]

😂😂😂

[@odyseuszkoskiniotis6266]

The what?

[@jonnybarnett2777]

Technically one doesn’t “use” the helium valve but I do understand the point you were trying to make

[@ChristianUtama]

Another use: *To count your heart rate (beats per minute)* When you detect the first pulse on your wrist, start the chronograph, keep counting and stop when you detect the 60th. Read the number on tachymeter. Example: from the 1st pulse to 60th pulse you take 40 seconds, it points to 90 in the tachymeter, so your heart rate is 90 bpm.

[@verbal_DK]

wouldn't be easier count to 6 beats and divide pointed value with 10?... or count to 12 beats and divide pointed value with 5?

[@ChristianUtama]

@@verbal_DK say that your heart beat is 90 bps, so the tachymeter should be pointing at 900 (if you use the divide by 10) but tachymeter scale max is 500. You can use division by 2, 4, 5 it means more calculation is done, but if you're okay with it then do it because it will be quicker too. I just want to show the basic of measuring heart beat and the easiest way to just read the result on the tachymeter scale.

[@verbal_DK]

@@ChristianUtama that's the reason why I wrote that you can also count to 12 beats and divide value with 5.

[@ranietsd1]

If your heart rate is 90 bpm, call a doctor ! Why not count your pulse for 60 seconds ? Then you don't have to calculate or to check the tachymeter.

[@ChristianUtama]

@@ranietsd1 normal heart rate range from 60-100 bpm. If your heart rate is 120 then it will only take half minute to measure it with this basic method. If you're good with division, you can use division by 2, 4 or even 5 to make it even quicker.

[@virtualRod]

so far the best explanation[s] on how to use the tachymeter on a timepiece...thank you Eric.

[@ternsjo]

+v Rod Hi, thanks for the comment! I'm glad it helped :) You might enjoy my other watch reviews and explanation videos on my channel.

[@virtualRod]

Erik Ternsjö not necessarily helped...I already knew, just trying to support a decent KZbin channel where many idiots belittle & degrade what they don't understand, I'll check your other vids. THANKS!

[@ternsjo]

Haha, alright, well thank you! :)

[@virtualRod]

Erik Ternsjö & by the way... very nice Omega timepiece indeed.

[@ternsjo]

v Rod Thanks. I made a second video of the vintage Omega from 1954 where I discuss the piece in more detail.

[@aarslanov8825]

It's been incidental to come across your explanation of the tachymeter function - I've enjoyed it immensely as I find your style of explaining things truly excellent!

[@michaelbauers8800]

Well done, and props for giving the formula the scale represents. That's really the key to understanding the scale, as it's really just a conversion from seconds to distance.

[@CGAWCChannel]

Great explanation!

[@ternsjo]

+Amateur Watch Collector Thanks!

[@schmanderich]

I think no one ever used this

[@PhilippeCarphin]

I'd be curious to see. I have a diver's watch with a rotating bezel and I use it to time all sorts of things or just set it to zero when I start something so I can see quickly how long I've been going. It's basically equivalent to remembering the time at which I started and doing a subtraction, but I can't live without it. Maybe people who have it and know how to use the tachymeter end up finding uses for it everywhere though it does seem less likely than for my dive watch bezel which has a simpler function.

[@ChuckBeefOG]

It was used for thousands of things in the late 1800’s/early 1900’s. Daily use faded into the 30’s but they are still used today.

[@LaMilk-69]

The tachymeter is resourceful, you provided an amazing explanation with intriguing examples to teach your audience, thank you 😊

[@TheAspenator117]

I just got a watch for my 21st bday with a tachymeter on it. This video has been immensely helpful in getting to know my watch and its functions. Thank you.

[@ternsjo]

Very nice! Happy the video helped!

[@chuckybaby1973]

Erik, your video was very simple, clear and easy to understand. I believe this video has helped many people understand how to get more out of their watch, thank you.

[@ternsjo]

Thank you for your feedback, much appreciated!

[@FIGNAS83]

best explanation on KZbin on how to use the tachymeter function. Subscribed!!!

[@ternsjo]

+FIGNAS83 Thank you for commenting, much appreciated! Hope you have a great day and stay tuned for more videos coming soon.

[@jeditello]

This has just been an amazing and easy to understand explanation with sufficient examples! Thank you 👍

[@Bulkman1337]

I've always had trouble understanding the Tachymeter scale until I watched your video. Thanks, Erik! :)

[@ternsjo]

+Erik Dahlgren Hi Erik, thank you for the feedback, I'm happy I could help!

[@civilengineer8407]

Very helpful video indeed and your examples made me (and everyone i suppose) comprehend the Tachymeter function in wristwatches well. Thanks a lot Erik.

[@PhobiaPhobic]

so glad to see youre back! i love watching your reviews!

[@ternsjo]

+PhobiaPhobic Thank you! Have a great day! :)

[@BijanIzadi]

I hope you know how valuable this explanation is to me, I literally never knew until watching this, thank you a ton!

[@amintaslneto]

Nice to see you back Erik. Great vid

[@ternsjo]

Thanks! Good to be back :)

[@DasSchmaus]

Explained simply and easy to understand graphics. Solid job!

[@ternsjo]

Thanks! You might like some of my other explanation videos on my channel related to watches.

[@theycallmejean]

Oh wow Erik, you did a top job at explaining that! Those were some great examples and illustrations!!

[@ternsjo]

+Jean-Silviu Dupouy Hi Jean, thank you, i'm glad you liked it! I'm happy with how it turned out :)

[@gogutzy]

thanks for the vid, it was a real eye opener. many say it's useless, but i'm more into old-school tech.

[@OrcinusLaryngologist]

I love this, sorta mind blown it took so long to take the time to grasp this. Thank you!

[@zebioh]

Thank you for a great and simple to understand explanation!

[@bv2225]

Great explanation thanks! Especially regarding production output, I wasn't aware of this application! Keep up the good work!

[@ternsjo]

Thank you for your feedback, much appreciated! Stay tuned for more videos ;)

[@CarstenDittrich2014]

Very good explanation - just what I needed for my work. Thanks much

[@neilpateldpt]

Was just gifted a nice Victorinox Chronograph for my graduation. Had to look this video up haha thank you

[@jsollien127]

Erik, your english is impeccable! I moved from Sweden to the US about 20 years ago and I still have an accent! BTW, great video too.

[@ternsjo]

Haha, great, thanks! Though, there’s nothing wrong with an accent! 😂

[@TheCaptain008]

I have two Seiko tachymeter watches. I rarely have a need for a tachometer in my life. But it is a fun novelty and a cool thing to understand if it's ever needed. The last of your lessons with production with watches and cars. I'm curious to try that at work with our ladies in production. They build padlocks. I'm going to low key see how much some do per minute. Thanks!

[@EliteHapkido]

easiest explanation found! great job.

[@ternsjo]

+EliteMartialArtOC Many thanks! You might enjoy my other explanation videos on my channel. Have a great day!

[@iandres2394]

Your watch is really cool bro, and your explanation was pretty useful.

[@ternsjo]

+Andres Gonzalez I'm glad you enjoyed the video. Thanks for commenting!

[@jorgeernestohigueroromero5570]

Congratulations!!! Exevcllent explanation!!! Thank you very much for being such a great teacher.

[@rag_man673]

I'm a little slow at math so I had to watch parts twice, but that said, if I can understand it (eventually, LOL) anybody can. Great explanation. Thank you so much. 👍

[@urosstankovic4887]

I just got new tissot watch and i try to understand this, thanks for explanation 😀

[@grailph]

thank you for this and also for giving more samples and not just for measuring speed.

[@gregorychang7692]

thanx for that.. great to know.. i will come back for sure to keep on using the examples you showed......

[@ternsjo]

Glad I could help! Let me know if you have any questions

[@JellyForSale]

This is AWESOME! Thank you! I never knew the tachymeter could be so useful!

[@ternsjo]

Thanks for commenting, I really appreciate your feedback. You might enjoy my other explanation videos on my channel, let me know! :) Hope you have a great day!

[@JJDEsq.]

How is it giving you a reading in km/hr and mph?

[@JellyForSale]

If you use one mile as your measurement it will be mph. If you use one kilometer it will be kph

[@ternsjo]

Hi, thank you for answering the question :)

[@ternsjo]

Like JellyForSale replied, it depends on your unit of measurement. The answer should be in the same units as the question if that helps.

[@SuperVeshi]

Thanks to whoever uploaded this video

[@andyblue001]

very nice explanation, the easiest to understand by the way

[@xnikolai09x78]

Thanks the examples really helped grasp its concept. It's easy now that I get it :D

[@JDMricist]

Very helpful, exactly what I was looking for. Thanks for the video!

[@ternsjo]

Glad I could help. Thanks for the comment!

[@CeebraBeats]

by far the best explanation arround! Thanks

[@ternsjo]

Thanks for the compliment, much appreciated. You might also enjoy my other explanation videos on my channel. Enjoy the rest of your day!

[@ImMora1]

So basically when you take the time it takes to do something and read it on the tachymeter scale, It tells you how many times that thing would happen in an hour? That is quite simple really. Now I might actually use it some time!

[@tehb1726]

Fantastic explanation, thank you!

[@tundeknops]

any idea why the bezel number stand backwards? if the numbers stood in the right order it would be easier to read if it could. i have a AP watch swiss made with tachymeter.🤔

[@the.otis.burger617]

That was well done, and easy to remember! Thanks!

[@jonmanilenio]

thanks, that was a bit easier to understand for me than the other videos i watched.

[@ternsjo]

Great, glad I could help!

[@fukutaichou1903]

Is it okay if i just find it aesthetically pleasing. Everything just flew above my head after usain bolt

[@mahamza86]

Very informative. I always wondered how this worked.

[@ternsjo]

+Hamza Khawaja Thanks, I appreciate your feedback

[@abh15funk]

Nice video ! Thanks for the explanation of Tachymeter ! 👍

[@fassenm6041]

Today I know what is Tachmeter. It is on my Casio watch for last ten years.

[@chef1arjunaidi]

Good, clear examples explained well

[@anthonycda9606]

Hey mate, I have a question for you. Since you are able to understand this tachymeter better than I do, maybe you can help me fix the problem with my watch. I have a Citizen Eco-Drive and the red arm which is for the tachymeter is not on 12 like its supposed to be. It's on the 14 sec to be exact. could you help me please? thank you.

[@PogU_4Life]

What if you measure the speed of the car on a race track on a portion that is 2km? Or 6.54km?

[@JumpingWatermelons]

ahhh thanks. That's interesting. Never knew there was a watch for measuring and doing calculations based on takt time

[@Boki199611]

Very useful explanation! :)

[@hpbunaes]

Thanks - nice, simple, practical explanation.

[@ternsjo]

Thanks for the comment and glad I could help. Best, Erik

[@MaximEriksen]

Love the vid man, keep up the good work!

[@1deadfire]

OMG... really good explanation, easy to understand thank you.

[@ternsjo]

+1deadfire Thank you for the comment, I appreciate it! You might also enjoy my other explanation videos on my channel. Hope you have a great day!

[@garynorris4648]

Superb. I have owned several analog watches with the tachometer feature and have often wondered what it was for. Thank you. SUPERB!

[@ari91629]

nicely explained,thanks for posting

[@ternsjo]

Thanks for your feedback, much appreciated. You might enjoy my other explanation videos on my channel :)

[@agrimsingh11]

which watch are u using in the video

[@boring5357]

Can you explain how to calculate on a square watch with a digital display of the time?

[@ComboBreakerHD]

0:29 why from approx 7 seconds? So they could fit the word tachymeter on the bezel?

[@daaam2160]

Have had my watch for 24 years and am just learning this🤐🔨

[@VerySeriousUser]

This was more than I hoped for!

[@ternsjo]

Great, happy you liked the video!

[@dhruvgarg9943]

This person is a gods gift.

[@TheGazza636]

Great.always wondered how to use this.had it on watch for years

[@HOLYLIFEIFY]

Tachy Scale and Proverbs 11:1 comes to mind here! Also 11-1 equals the track and field championship I experienced winning when in 10th grade! With this here in 2020 I have been (B)ouncing (S)pikes pertaining to while on the track sprinting at the placing of a step it should bounce it's steps for greater speed. Terrill TC!

[@indragums]

This is very clear explanation. Thank you.

[@ternsjo]

Glad it helped!

[@nikolascha27282]

Before that video i had no idea how to use a tachymeter. But with that video it get very clear to me that i still dont understand it

[@manoman0]

Ok, It's that easy to explain the function. You, sir, you have it....thank you!

[@ternsjo]

I'm glad I could help. You might also enjoy my other (geeky) explanation videos on my channel :)

[@bamchel]

Superb explanation. Thank you!

[@oklahomahank2378]

I did in fact use this at the MotoGP in Austin. I used google maps to measure some intervals on the track. I must admit it was sort of showing off.

[@Frenk33]

That Omega Speedmaster Racing 40mm (released in 2012) is an absolute gem!

[@alijan634]

Best explanation ! Thank you

[@drbud7257]

Great explanation

[@mkmuaqibizzuddin6885]

So.. Only frequencies and speed in mile and kilometres? I saw once a complete digital watch have these. What's up with that???

[@ShubhamGupta-gk1yu]

Still couldn't get. Suppose m at rest and start tachymeter.it will point at 120 after 30 seconds. Now i m in a plane and after 30 seconds it will again reflect 120.what does that mean. As in ist i was at rest and 2nd moving at speed of around 1000kmph.

[@lonefather]

Well, I bought a watch with the tachymeter, 22 years ago, and did not know what it's for. Now I know at least the theory of this, after watching your video made 4 years ago. Anyway, that's a clear enough explanation and I may use it in my next driving (only if I can do the start/stop within one minute with my hands on the wheel).

[@cessealbeach]

Very Good Examples Thanks

[@Cheatcoe]

This is a feature they have as a apple watch face. Thanks for the explanation. I might want to use it.

[@johnrogers2957]

Thank Erik clear explanation

[@roberterwin9514]

Excellent explanation.

[@thiago_thesaint]

i dont get how it will know if you are measuring mph or kmph?

[@DannyWohl]

I found a tachymetre ferrari watch in my car i bought! I wonder if it is worth much? a couple of the hands are broken...

[@MrObiwan1]

That Speedmaster is stunning :)

[@josephzacharychong4708]

For example 1 and 2, wouldn't you then need to convert 1 mile to kilometers, ased on the fact that you converted 200m to a kilometer for example 3?

[@rafatlatif544]

If I walk one hour then can I calculate my distance and speed

[@bobdehuisbaas1]

Finally I get what these are used for, now I want a watch that has one! Nice speedmaster btw, love the yellow accents

[@ternsjo]

Thanks for commenting. I'm glad the video helped. You might enjoy my full review of this Speedmaster on my channel :) Hope you have a great day!

[@MrDidaxi]

Useful vid. Many thanks. 👌🏻👍🏻👋🏻

[@finnk9360]

Brilliant video. Superb explination

[@ternsjo]

+Finn Kahmann Thanks for the compliment, much appreciated!

[@Chewy7575]

Another good one. Thanks again.

[@ternsjo]

Glad it helped. Thanks for the feedback.

[@augieguerra503]

Definitely helped. Thanks.

[@DrstaCreations]

thank you so much for the valuable information .

[@stuartgalloway8674]

I got most of this but just one question, where on the tachometer should I start it when timing?

[@oklahomahank2378]

The chronometer does the timing. It starts at zero aka the 12 o’clock.

[@sknygames]

Are tackymeters measured only in km and not miles?

[@blazeracer1]

That's cool. Good explainations. I'm gonna use mine on something.