Fuel log app
Track Every Fill-Up. See Your Real MPG.
Maintory is a calm fuel log app for iOS. Log a fill-up in 10 seconds, and the app computes your real-world MPG (or L/100 km) between full tanks — automatically, in the same timeline as the rest of your car's life.
Why log fuel?
Fuel is the most frequent expense most car owners have. Logging it does three things at once: tracks a meaningful slice of your monthly spend, gives you real-world MPG (not the optimistic number on the window sticker), and quietly creates the early-warning system for a car that's starting to drink more than it used to.
A 10–15% drop in MPG over a few months is one of the first signals of a dragging brake, an oxygen sensor failing, or under-inflated tires. If you're not logging, you won't notice until the check-engine light shows up — or until you compare your gas-station receipts six months later and realize the numbers crept up.
The "full tank" method (and why it matters)
The most accurate way to measure real-world fuel economy is the fill-to-fill method: every time you fuel up to a full tank, you log how many gallons (or liters) went in, and the odometer reading. The distance between two full fills, divided by the fuel added at the second fill, is your true MPG for that period.
Maintory has a one-tap "full tank" toggle on every fuel entry. When you mark a fill-up as full, the app computes the MPG since your last full fill and adds it to a chart. No spreadsheets, no manual math.
What a good fuel log gives you
- Per-fill economy — how each tank performed, with date and odometer.
- Trends over time — your MPG month-over-month, season-over-season.
- Cost per mile from fuel alone — your $/mile, separate from insurance and depreciation.
- Annual fuel spend — the number that lets you decide if a more efficient car is worth it.
- Searchable history — when you last filled up at a particular price, or how much you spent in July.
Why an app, not a spreadsheet
Anyone can build a fuel-log spreadsheet. Almost no one keeps it up for more than two months. The reason is friction: opening a sheet, finding the right row, switching keyboards to enter a decimal — every step is a tax on consistency. The first time you skip an entry, the MPG chart goes wrong, and the moment the chart is wrong, the app becomes pointless.
A good fuel-log app removes that friction. Maintory: open, tap +, pick Fuel, enter amount and gallons, tap save. Six seconds. Done.
Related guides & calculators
Watch your real-world fuel economy unfold.
Log every fill-up and Maintory plots the trend — MPG or L/100km, your choice.
