Cardio calculator
Yo-Yo intermittent recovery test calculator
Convert a Yo-Yo IR1 or IR2 distance into VO₂ max — the standard aerobic field test for football, rugby and other team sports. Free, instant, no sign-up.
IR1 starts at 10 km/h and suits any squad. IR2 starts at 13 km/h and only tells you anything about already well-trained athletes.
A whole number of 40 m shuttles — 1,240, 1,280, 1,320 …
Repeated-sprint capacity is trainable in weeks — the coach builds the sessions that do it.
What is the Yo-Yo intermittent recovery test?
Twenty-metre shuttles run to a beep that speeds up as the test goes on — but with ten seconds of jogged recovery between each one. That recovery is the whole point. It makes the test look like a match rather than a steady run, and it is why Yo-Yo scores track high-intensity running in games better than a continuous test does. Your result is the total distance you covered before missing two beeps.
How this calculator works
Bangsbo, Iaia and Krustrup (2008) published the conversions from distance to aerobic capacity. For IR1, VO₂ max = distance in metres × 0.0084 + 36.4. For IR2, VO₂ max = distance × 0.0136 + 45.3. The two are fitted on their own protocol and are not interchangeable — running an IR2 distance through the IR1 line would understate a strong athlete badly, so this page keeps them separate.
Running the test properly
Mark 20 m for the shuttle and 5 m behind the start line for the recovery jog. Players run out and back on the beep, then jog the recovery lane and are back on the line for the next one. A player is finished when they twice fail to reach the line in time — one miss is a warning, not the end. Test the whole squad on the same surface and the same shoes, because grass, artificial turf and an indoor court do not give the same distance.
How accurate is it?
As a VO₂ max estimate it is indicative rather than precise — the conversion is a population regression and an individual can sit either side of it. Its real strength is as a repeated measure: the same player, same surface, six weeks apart, gives a change you can trust and act on. Motivation matters more here than in a continuous test, so run it with a group and a clock rather than alone.