Fuel & Range Planner

Know your actual range before you leave the trailhead. Enter your tank, loaded MPG, terrain type, and aux storage — the planner outputs a safe range that keeps a reserve buffer and accounts for how much terrain degrades fuel economy.

Vehicle & fuel setup

gallons — use actual fill capacity, not sticker
on-road MPG with your current build, gear, and passengers
gallons — jerry cans, aux tank, rotopax (enter 0 if none)
% of usable fuel kept back — don't plan past this point

Terrain type

Multipliers are practical averages — your actual consumption varies with tire size, gearing, line choice, and conditions.

Planning range

—
miles — safe planning range
Plan your route to turn around before this point
—
miles — theoretical max
If everything goes perfectly — don't plan to this
Fuel allocation
Usable for route Aux storage Reserve (keep back)

Why loaded MPG matters more than the sticker

Highway MPG numbers are for a stock, empty vehicle at cruise. On trail you're carrying gear, passengers, and water — plus you're in low range, running aired-down tires, and idling at obstacles. A stock XJ rated at 18 MPG highway might see 12 MPG loaded on dirt and 8–9 MPG in deep sand. Measure your actual loaded MPG on a similar trip before relying on this calculator for a remote run.

The terrain multiplier is applied to your loaded MPG, not the sticker. If your XJ gets 12 MPG loaded on pavement, sand applies a 0.65× factor → ~7.8 MPG effective. That's the number the range calculation uses.

Aux fuel in jerry cans or roof-rack storage adds to your total supply but shouldn't be counted toward your usable reserve without accounting for the hassle of transferring it at trail speed. Factor that into your buffer selection.