Time Signature Converter
Rebarring a passage is easy to get wrong because note names hide the arithmetic. Three-four and six-eight hold exactly the same amount of music per bar despite looking nothing alike, while four-four and five-four do not divide into each other at all. Working in a common subdivision settles it, and this shows the total in semiquavers so you can see the conversion is genuinely length-preserving.
What this generator does
Measures a passage in semiquavers, then divides by the length of a bar in the target meter, reporting how many bars that is and whether the division comes out whole.
How to use this tool
- Generate a conversion between two time signatures.
- Read the total in semiquavers — it is the same on both sides.
- Check whether the conversion comes out as whole bars.
- When it does not, expect to tie a note across a barline.
Understanding the controls
- Generate
- Produces a conversion between two of the common time signatures — 4/4, 3/4, 6/8, 2/2, 5/4, 7/8, 9/8 and 12/8 — across a passage of 2 to 16 bars.
- Seed
- Any word reproduces exactly the same conversion.
Common use cases
- Rebarring a passage into a different time signature
- Checking whether two meters divide into each other cleanly
- Working out how long a section runs in a new meter
- Teaching why 3/4 and 6/8 hold the same amount but feel different
- Setting the same worked example twice from a seed
How this generator works
Everything is converted to semiquavers first, because that is the only way to compare meters whose beat units differ. A bar of 6/8 holds twelve of them and so does a bar of 3/4, which is exactly why those two convert one-to-one despite grouping the beats completely differently. The check confirms the converted bars come back to the same total, which is what makes the conversion honest.
Randomness and fairness
The two time signatures and the bar count are random; the conversion is exact arithmetic. A seed reproduces the same example exactly and is therefore explicitly not cryptographically secure. Without a seed the browser's cryptographically secure generator is used.
For how randomness is produced across the whole site, see how Generate Random works.
Limitations and good to know
- Duration only. It says nothing about where the accents fall, which is the whole difference between 3/4 and 6/8 in practice.
- Common time signatures rather than arbitrary ones.
- Tempo is assumed unchanged. Rebarring often comes with a tempo change, which alters real elapsed time.
- A fractional answer tells you a tie is needed but not where to put it.
- Conversions are not stored between visits; seed one you want again.
Privacy and your data
The conversion is computed in your browser and nothing about it or your seed is transmitted or stored.
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