Volume Matching Calculator — ReppySetGo

Let's say you usually rip 10 reps with a 20kg weight on a given exercise. You're on holiday and you're using the hotel gym. They only have 25kg weights. Put those numbers in this tool and it will tell you 8 reps will get you the same volume. Good enough in a pinch.

Volume, in this context, means total weight moved: reps multiplied by load. It's a blunt measure of training stimulus, and it has real limitations. Changing the weight-to-reps ratio — especially dramatically — can create different kinds of stimulus. Broadly speaking, higher reps with lighter weight tends to favour muscular endurance while lower reps with heavier weight tends to favour strength. Two combinations that produce equal volume are not exactly "the same". So this is not an everyday-use tool.

But let's say you just moved permanently to a different gym, and their equipment has different weight selectors, plates, or dumbbells. This tool will let you reprogram your workout to the nearest-neighbour so you can pick up more-or-less where you left off. If you're scientifically minded and you want to run a few tests to compare high reps versus low reps, or machines versus free weights, this can help with that too.