Programmable timer web app (for gym workouts or stretching sessions)
Over the last couple of months, I’ve been building a timer web app for myself that I use for workout and stretching sessions. My main use-case is gym routines that consist of repeatable sequences, e.g. where you are holding certain positions for a set time (rinse and repeat). The app counts down the program, beeps, and reads the activities out loud. Two things (I suppose) are special about it: - The timers are “programmable”, so you can freely express your own routines and procedures in a declarative notation. - The app is all static (no backend): the entire program is encoded in the URL and…
In plain words
This is a programmable timer web app designed for gym workouts and stretching routines. Users define custom workout sequences in a plain text format, and the timer counts down while providing audio cues and voice announcements for each activity. The app runs entirely in the browser with no backend, storing complete programs in the URL for easy bookmarking and sharing via QR code. It's built for people who perform repeatable exercise sequences and need a flexible way to manage timing across multiple sets.
written from the facts on this page · September 2026
From the sources
A programmable timer web app, e.g. for gym workouts or stretching sessions. Timer programs are specified in a plain and flexible text format, and can be stored or shared via URL or QR code.
In the maker’s words, at launch
Over the last couple of months, I’ve been building a timer web app for myself that I use for workout and stretching sessions. My main use-case is gym routines that consist of repeatable sequences, e.g. where you are holding certain positions for a set time (rinse and repeat). The app counts down the program, beeps, and reads the activities out loud. Two things (I suppose) are special about it: - The timers are “programmable”, so you can freely express your own routines and procedures in a declarative notation. - The app is all static (no backend): the entire program is encoded in the URL and can be bookmarked or shared/transferred via QR-code. You can check it out at https://timer.jotaen.net, optionally with a demo program pre-loaded: https://timer.jotaen.net/#demo. Source code is at https://github.com/jotaen/timer. I’ve also written up a small behind-the-scenes on my blog: https://www.jotaen.net/SAKxq
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