Sitting Offset Calculator
Work out how much moderate activity your sitting load calls for, how big the gap is right now, and how often to interrupt the sitting itself.
What this means
Your sitting-break plan
How the target is calculated
Most activity advice gives everyone the same number regardless of how much they sit. The research does not work that way: the amount of activity associated with offsetting a sedentary day scales with how sedentary the day actually is. This calculator starts from the World Health Organization floor and moves it upward with your sitting load.
The baseline
The WHO 2020 guidelines recommend 150–300 minutes of moderate-intensity activity per week, or 75–150 minutes of vigorous activity, for all adults. That lower bound works out to roughly 22 minutes a day, and it is the floor this tool starts from for someone who barely sits.
The sitting adjustment
From there the target rises with sitting hours. The anchor is a 2020 meta-analysis of nine studies covering 44,370 people wearing activity trackers, which found that at around 30–40 minutes a day of moderate-to-vigorous activity, the association between high sedentary time and mortality risk was no longer meaningfully different from that of people with low sedentary time. A separate analysis of occupational sitting published in 2024 pointed the same direction from another angle: people who predominantly sit at work needed roughly 15–30 extra minutes of daily activity to match the risk profile of those who do not.
So the tool scales from about 22 minutes a day at four hours of sitting up to roughly 40 minutes at ten hours, then flattens. It is deliberately a target range rather than a precise prescription, because the underlying studies disagree on the exact number for a reason worth understanding.
Why you will see 30–40 minutes in one study and 60–75 in another
An earlier and widely quoted 2016 analysis of over a million people concluded that 60–75 minutes a day was needed to eliminate the excess risk associated with sitting more than eight hours. That looks like it contradicts the 30–40 figure, but the gap is largely a measurement artefact: the 2016 work relied on self-reported activity, while the 2020 meta-analysis used device-measured activity. People consistently over-report how much they move, so a self-reported hour and a device-measured half hour can describe the same person.
This calculator uses the device-measured basis, which means the number it gives you is the one to compare against a watch or phone rather than against your own estimate. If you are estimating by memory, assume your real figure is lower than it feels.
Why the break plan matters separately
The most counter-intuitive finding in this area is that sedentary behaviour and physical inactivity are not the same problem. You can hit your activity target and still spend eleven hours sitting, and the sitting appears to carry its own cost. Research on interrupting sitting has found that standing or moving for as little as two to five minutes every 30 to 60 minutes improves glucose handling — a benefit a single workout does not deliver.
That is why the tool returns two separate outputs. The minutes target addresses inactivity. The break plan addresses sedentary time. Closing one does not close the other.
Targets by sitting load
The table shows the daily target this tool produces, so you can sanity-check your own result.
| Sitting per day | Daily target | Weekly equivalent | Typical pattern |
|---|---|---|---|
| 4 hours or less | 22 min | ~150 min | Active job, on your feet |
| 6 hours | 27 min | ~190 min | Mixed desk and moving |
| 8 hours | 32 min | ~225 min | Standard desk job |
| 10 hours | 38 min | ~265 min | Desk job plus commute and evening |
| 12 hours or more | 43 min | ~300 min | Very sedentary day |
What this tool does not do
- It does not predict your personal risk. The studies behind it describe population averages across large groups, not individual outcomes.
- It does not replace reducing sitting. Hitting the minutes target is not permission to sit longer — the two effects are separate, which is the whole point of the break plan.
- It does not account for sleep. Sleeping is not sedentary time in this sense; count only waking hours spent seated or reclining.