How much pressure for MTB?
Mountain bike tyres run at a fraction of road pressure because they are doing a different job: a big-volume tyre at low pressure wraps around roots and rocks for grip and soaks up hits your suspension misses. The trade-off is protection — go too low and you get tyre roll in corners, rim strikes, and burping. The right number is the lowest pressure that still supports the tyre under you.
This calculator sets each tyre to about 15% drop under its share of your weight, then accounts for the huge air volume of a modern MTB tyre. The front runs a touch lower than the rear for cornering grip, since it carries less load and is not driving. It is the same engine as the Route Companion app, and like everywhere it errs slightly low — but on the trail, casing support and inserts matter, so treat the number as a floor to fine-tune upward if you feel the rim.
Typical MTB pressures by rider weight
| Rider (incl. bike + kit) | Front | Rear |
|---|---|---|
| 60 kg | 12 psi | 12.5 psi |
| 70 kg | 12.5 psi | 14 psi |
| 80 kg | 14 psi | 16 psi |
| 90 kg | 15 psi | 17.5 psi |
| 100 kg | 16.5 psi | 19.5 psi |
Starting points for a 2.25 in (57 mm) tubeless trail tyre, steady pace, 29 in wheels. Bigger tyres and inserts let you go lower; use the calculator above for your exact width.
Adjust for the terrain and setup
| Smooth, flowy trail | The calculator number, or a touch lower for maximum grip. |
| Rocky, rooty, technical | Add 1–2 psi, or fit a casing insert so you can keep it low without rim strikes. |
| Bigger tyre (2.4 in+) or inserts | You can run lower than a 2.25 in tyre at the same weight; enter your real width. |
Common questions
Why is MTB tyre pressure so low?
Mountain bike tyres have several times the air volume of road tyres, so they reach the same support at much lower pressure. Low pressure lets the big tyre deform around obstacles for grip and comfort, which is the whole point off-road.
What pressure should I run in MTB tyres?
For an 80 kg rider on a 2.25 in tubeless trail tyre, roughly 14 psi front and 16 psi rear is a sensible start. Lighter riders and bigger tyres go lower; use the calculator for your weight and width.
Should the front MTB tyre be lower than the rear?
Usually yes. The rear carries more weight and takes the drive and braking forces, so it needs a bit more pressure. A slightly softer front adds cornering grip and traction where you steer.
Do I need tubeless for low MTB pressures?
Effectively, yes. The pressures that make an MTB tyre grip would pinch-flat a tube almost immediately. Tubeless also lets sealant close small punctures, which is why nearly all trail riders run it.
When should I use a tyre insert?
If you keep striking the rim or burping at the pressure that gives you the grip you want, an insert lets you run lower safely by protecting the rim and supporting the sidewall. It is the usual fix for heavier or more aggressive riders.
Other disciplines
Set your tyres for the trail ahead.
The Route Companion app runs this engine on your planned rides and surfaces it in the pre-ride checklist with weather, clothing, and fueling — so your setup matches the day before you roll.