Fleet Utilisation Calculator
How well a fleet is used — the share of available vehicle-days actually driven, the cost of every vehicle-day whether used or idle, the cost of the idle days, and how many vehicles the same work would need at a target utilisation.
A fleet of twenty vans available six days a week offers about 6,000 vehicle-days a year; if 4,200 are driven, utilisation is 70% and the other 1,800 are paid for and parked.
How the fleet utilisation calculator works
A fleet of twenty vans available six days a week offers about 6,000 vehicle-days a year; if 4,200 are driven, utilisation is 70% and the other 1,800 are paid for and parked. The fixed cost per vehicle — lease, insurance, registration — is spread over the used days, so low utilisation raises the cost of every working day. The vehicles needed at a target utilisation is the honest fleet size.
Formula: utilisation = vehicle-days used / vehicle-days available; vehicles needed = days used / (available days per vehicle × target)
Worked examples
| Inputs | Fleet utilisation | Note |
|---|---|---|
| Twenty vans, 4,200 days driven | 70% | 70% |
| A tight fleet | 87.5% | 87.5% |
| Half idle | 50% | six vehicles too many |
FAQFrequently asked questions
What is fleet utilisation?
Vehicle-days driven as a share of vehicle-days available. It is the first number to look at in a fleet review, because fixed costs are paid on every vehicle whether it moves or not.
What utilisation is good?
Seventy to eighty-five per cent for a working fleet. Above that there is no cover for breakdowns and peaks; below 60 there are vehicles that should be sold or shared.
What counts as an available day?
Days the vehicle could be driven — working days less scheduled maintenance. Three hundred a year is a six-day operation; 250 is a five-day one.
What is in the fixed cost?
Lease or depreciation, insurance, registration, telematics — everything paid regardless of use. Fuel, tyres and servicing vary with distance and belong in the per-kilometre cost instead.
How do I raise utilisation?
Pool vehicles across teams, retire the least-used, use short-term hire for peaks, and schedule maintenance for idle days. Telematics data makes the idle days visible.
Where these figures come from
- ISO 4000 / ETRTO — tyre designation and dimensions — the width / aspect ratio / rim marking this page decodes
- Australian Government — Green Vehicle Guide — the official Australian fuel consumption database
Last checked: September 2026. Tyre dimensions follow the ISO metric marking standard; engine formulas are the standard textbook forms.