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Weighlifting tracker app for coders.

The most powerful weightlifting app ever. Build weighlifting programs, with any progression and deloading logic, be in control of your progress.

Or choose one of the existing programs, like GZCLP or 5/3/1 that helped thousands of lifters to get bigger and stronger.


One of the most important concepts in weight lifting is progressive overload. It means that you should constantly challenge yourself by increating the weights or number of reps, and your body would respond to it by getting stronger and bigger.

When you start lifting, you can increase the weights every week, but in several months you will reach a point where you can't increase the weights so often. That's when you need to switch to a new program, try new patterns of periodically adding and reducing weight. There's a lot of various programs created by experienced weighlifters, who found ways to keep progressing. There're GZCLP by Cody LeFever, 5/3/1 by Jim Wendler, nSuns LP by u/nSuns - different people like different programs, and different programs work differently for different people.

Liftosaur allows you to try all those programs, modify them, and keep track of your progress no matter what program you use. It's a companion of your weightlifting journey, and it is there for a long run. It defines all those programs using built-in scripting language Liftoscript, which is a very simple scripting language, that looks like JavaScript.

You don't have to use or know about it, you can stick to built-in programs, but with it you can tailor the programs for you. E.g. Squats progression and deload logic in Stronglifts 5x5 could be expressed in Liftoscript as:

if (completedReps >= reps) {
  state.weight = state.weight + 5lb
} else {
  state.failures = state.failures + 1
if (state.failures > 2) {
  state.failures = 0
  state.weight = state.weight * 0.9

And you can modify it in any way you want. E.g. you may change increments to 2.5lb, change max number of failures to 5, you may completely change the logic to anything you want. You have access to completed sets, reps, weights, you can create any state variables you want. There's a bunch of example programs written in the same Liftoscript language from

Read more or watch the video tutorial in Documentation

Built-in workout programs

And of course you can build your own program as well!