Tools Autoregulation
RIR to weight calculator
Turn a target effort into a number on the bar. Enter a recent set, then how many reps you want and how many you want to keep in reserve, and get the working weight in pounds and kilograms plus the percent of 1RM it lands on. Nothing leaves your browser.
RIR (reps in reserve) is how many more reps you could have done before failure. Picking a target RIR is how you control effort without maxing out, but it leaves a question: what weight actually puts you there? This calculator answers it. It estimates your 1RM from a recent set, then works backward through the same Epley relationship the Anneal app uses to find the load for your target reps and RIR.
Find your working weight
How to read the result
The weight is the load that should leave your target reps in reserve on a set of your target reps. It is shown in both units, with the percent of 1RM so you can sanity-check it against how you usually train. The estimate stays reliable while your target reps plus RIR stay at or below 12; past that the calculator still gives a number but flags it as a rough starting point, since the 1RM model loses accuracy at high rep counts.
For the scale itself and how it maps to RPE, see RIR explained. To estimate the 1RM this is built on, or to see the full percentage table, use the 1RM calculator.
Common questions
What is RIR?
RIR stands for reps in reserve: how many more reps you could have done before failure when you stopped a set. RIR 0 is failure, RIR 2 means you had two more in the tank. It is a simple way to gauge and control effort set to set without testing your max.
How does RIR set my weight?
A set of your target reps stopped with your target RIR is, in effect, a set whose reps to failure equal target reps plus target RIR. The calculator runs that total back through the Epley model against your estimated 1RM to find the load. So aiming for 8 reps with 2 in reserve prescribes a weight you could grind for about 10 before failure.
What RIR should I train at?
Current evidence favors most working sets landing around RIR 1 to 3 for hypertrophy and general strength, close enough to failure to drive adaptation while leaving room to recover and repeat. Training all the way to failure on every set still has defenders, but it adds fatigue fast. Heavier strength work often sits at lower RIR on top sets; lighter or higher-volume work can sit a touch higher.