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Musician's Pocket

Musician's Pocket, a small reckoner that computes in your browser and stores nothing. No account, no cloud, no telemetry.

Live · runs in your browser · no network

This is not a screenshot. It's the real tool, running right here: go on, put something in it.

Open the demo full-screen: /demos/musicians-pocket.html

Forged into a knife, this tool ages with use: the blades you reach for wear soft, entries you tend keep their bloom, and the years travel with the file through every reforge.

Somewhere in every rehearsal, somebody asks what the tempo works out to, and everybody looks at the drummer. Musician's Pocket does the small maths of music — the reckonings that connect beats, time, and pitch — right there in the page. It computes and keeps nothing, so the only thing you take from practice is the practice.

KindReckoner · computes, stores nothing
CategoryReckoners
Weight1
Manual:

Standing facts

In ten years

Musician's Pocket computes; it doesn't hoard. Open the file in 2036 and it will do the same arithmetic it does today, because the arithmetic is written into the file and nothing about it needs a server to agree.

If Offline.Ltd closes tomorrow, nothing on your machine notices. That isn't a marketing promise; it's simply what a file is.

Getting your data out

There is nothing locked in to get out: copy the numbers, or keep the file. Either way you owe no one a request form. No export queue, no "we'll e-mail you a link within 48 hours", no format that only one vendor can read.

Copy the file to a USB stick, a NAS, a folder your devices already sync. It runs on Windows, macOS, Linux, Android and iOS, online or off, because a browser is the only thing it ever needed.

Who else sees this

Nobody. Musician's Pocket works out its answer in your browser and forgets it the moment you close the tab: there is no store to breach, because nothing is stored. There is no account, no telemetry, no analytics, and no code in the file that opens a network connection, pull the cable and watch it carry on working. How privacy works across the Reckoners tools →

Questions people ask

01

What kind of calculations does the Musician's Pocket do?

The workaday arithmetic musicians actually need — the sums that connect tempo, time, and pitch — computed instantly. It is a pocket calculator that happens to speak music.

02

Does it work offline in a rehearsal room with no wifi?

Yes, which is most rehearsal rooms. It is a single HTML file that runs in your browser without a connection, computes on the spot, and stores nothing. Nothing you work out ever leaves the page.

03

Is it for professionals or beginners?

Both, since the arithmetic is the same at every level — only the stakes change. Bedroom producers, choir directors, and gigging players all end up doing the same sums; this just does them faster.

Go deeper on Musician's Pocket

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Fits your knife at weight 1. Nothing here is final, Knife follows Life. Reforging within your tier is free, forever. Add it, drop it, reforge it later; the file stays yours either way.

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