What is the best gas mileage app for iPhone in 2026?

The short answer: six gas mileage apps compared

I build WrenchTime, one of the apps below, so read this knowing that. Fuelly, Fuelio, Drivvo, Road Trip MPG and Simply Auto are trademarks of their respective owners. WrenchTime is not affiliated with, sponsored by or endorsed by any of them. Every claim below links its source and was checked on October 26, 2026.

A gas mileage app is a fuel log: you enter each fill-up with the odometer reading and the gallons, and the app works out MPG and what the car costs to run. The table compares six of them on what decides the choice: the free version, the platforms, whether you need an account, and how each one handles a partial or a missed fill-up.

Each app below, WrenchTime included, is named for the need it suits, so you can match it to yours. Apps that track business mileage for taxes are a different list, our best mileage tracker apps.

Sources: the US App Store listings of Fuelio, Drivvo, Road Trip MPG, Fuelly and Simply Auto, the Fuelio FAQ and the Drivvo FAQ, checked October 26, 2026.

How does a gas mileage app calculate MPG?

A gas mileage app calculates MPG the way fueleconomy.gov describes it: divide the miles traveled since the last fill-up by the gallons needed to refill the tank. The method needs two consecutive fill-ups where the tank is filled completely. Outside the US the same method gives L/100 km, the liters used for every 100 km driven.

Two common mistakes break that number. fueleconomy.gov warns that "if you do not fill up your tank completely, your MPG estimate will not be accurate", and that a fill-up you forgot to log needs a gap record, or "the number of miles traveled will be too high". This is the column that matters most in the table above: an app has to know which fill-ups were full and which interval is missing an entry.

Our guide on how to calculate gas mileage by hand works through the formula with examples, including partial fill-ups and the cost of a trip.

Choose Fuelio if you want a free fuel tracker app with no account

Fuelio, by Sygic, is a free fuel log for iPhone and Android. Its App Store listing says no account is required and the app shows no ads, with data kept on the device and an optional iCloud Drive backup. It covers several vehicles and fuel types, shows gas prices from users and third-party sources, also in CarPlay, and imports and exports CSV. On October 26, 2026 it averaged 4.5 from 170 ratings.

Fuelio's FAQ states that it uses a full-tank algorithm and needs at least two full fill-ups before consumption appears in its stats. Fuelio Pro, a monthly or yearly purchase, adds more expense categories, maintenance reminders, offline receipt scanning and extra reports. Our Fuelio and WrenchTime comparison goes into more detail. It may suit you better than WrenchTime if your household also uses Android.

Choose Drivvo if you need Android, iPhone and the web on one account

Drivvo, by Cristian Cardoso, is a car expense tracker with a fuel log, and its FAQ says it is available on Android, iOS and the web. An account is required: it identifies your profile, stores the data and lets you log in from another device or a browser. On October 26, 2026 its App Store listing averaged 4.7 from 979 ratings.

Drivvo calculates consumption between two full fill-ups, counts partial fills in between toward the fuel total, and offers a "Missed previous refueling?" option so a forgotten entry does not distort the figure. The free plan has unlimited fill-ups, up to 2 active vehicles, reminders and reports, with ads. The Individual and PRO plans remove ads and add vehicles, attachments and data export. It may suit you better if you want the same log on Android or in a browser.

Choose WrenchTime if you want the camera to log the fill-up for you

WrenchTime, a car maintenance app for iPhone, is built to get the number right. It computes tank-to-tank economy from fill-ups marked as full, lets you flag a missed fill-up so that interval is left out instead of producing an impossible figure, and warns when your economy drops against your own history. It keeps the two gallons apart, so US MPG and imperial MPG never mix. The fuel economy tracker guide explains the method.

Of the apps on this page, WrenchTime is the one that reads the pump's own LED display, not just the paper receipt: among the others, the only scanning their cited App Store listings and FAQs describe is Fuelio's paid tier's on-device receipt scanning (checked October 26, 2026).

It is also the one of the six that goes past the fuel log in two ways their own App Store pages, checked October 27, 2026, do not mention. It reads the engine's live data over an OBD-II adapter, free, and with WrenchTime Pro it has an Apple Watch app, where a fill-up can be logged from the wrist.

Logging a fill-up is mostly pointing the camera. With WrenchTime Pro, aim it at the pump display, a charger screen or the paper receipt and it reads the volume or energy, the total cost and the price per unit. It uses on-device Vision text recognition, with a seven-segment decoder for LED pump displays, and Apple Intelligence on supported devices.

A plausibility check cross-checks the three values against each other, so a misread digit is caught, and a confirmation sheet shows what was read before anything is saved. Everything runs on the iPhone: no photo or number leaves it, and there is no per-scan fee or extra service on top of Pro.

The same log holds maintenance with reminders by date or mileage and, with a paired car stereo, trips recorded on their own. There is no WrenchTime account and no ads on either tier: data stays on your iPhone and in your own iCloud. With WrenchTime Pro, a CSV export from Fuelly, Drivvo or Fuelio can be imported.

It is also built to feel like part of the iPhone. WrenchTime is written natively in SwiftUI for iOS 26, with Liquid Glass and the Dynamic Island: a trip being recorded shows its distance and time in a Live Activity on the Lock Screen and in the Dynamic Island, and 9 Home Screen and Lock Screen widgets, some with WrenchTime Pro, keep the odometer, recent fill-ups and the month's spending a glance away.

CarPlay and an Apple Watch app, where a fill-up can be logged from the wrist, come with WrenchTime Pro. The iPad gets a permanent sidebar, the dark theme is calibrated for OLED rather than inverted from the light one, and Pro adds 30 accent themes. There are no ads on either tier and no account: your log stays in your own iCloud.

Choose Road Trip MPG if you want a one-time purchase on iPhone

Road Trip MPG, by Darren Stone, is an iPhone app sold as a one-time purchase. Its App Store listing lists no in-app purchases and says there are no ads, subscriptions or recurring fees, with Family Sharing for up to six members. Its privacy label reads Data Not Collected, and sync runs through iCloud or Dropbox. On October 26, 2026 it averaged 4.9 from 629 ratings.

The listing says its fuel economy tracking covers partial, same-day and missed fill-ups. Around the fuel log it keeps unlimited vehicles, a service log with reminders, a tire log, expenses, a trip cost calculator and distance to empty, with CSV import and export. Its listing describes an iPhone-only app. It may suit you better if you prefer a one-time purchase with nothing to buy afterwards.

Choose Fuelly if you want a log that syncs with a website

Fuelly, by Fuelly, LLC, is an iPhone app that syncs with the Fuelly.com website, according to its App Store listing. Each fill-up records the miles, gallons and price per gallon, and the app charts MPG, gas price, gas spend and service spend across several vehicles, with service reminders and CSV reports by email. It reads in MPG, L/100km and km/L. On October 26, 2026 it averaged 4.7 from about 30,000 ratings.

Fuelly is free with in-app purchases. Fuelly Premium removes ads, adds photo and PDF attachments to records and auto-completes locations. The listing's description does not detail how partial or missed fill-ups are handled. It may suit you better if you want your log on the Fuelly.com website.

Choose Simply Auto if you want fuel, trips and tax logs together

Simply Auto, by Mrigaen Kapadia, keeps fill-ups, maintenance, mileage, expenses and trips in one log. Its App Store listing says it supports partial fill-ups, compares fuel efficiency by octane, brand and station, logs EVs in kWh, and keeps tax-deduction and rideshare logs, with CSV import and export. On October 26, 2026 it averaged 4.1 from 870 ratings.

The app is free with two paid tiers. GOLD adds instant cloud backup, GPS trip tracking, receipt backup to Google Drive and web access; PLATINUM adds unlimited vehicles and drivers and automated weekly or monthly reports. The listing shows several purchase options for the paid tiers, so check the purchase screen for the current ones. It may suit you better if you need tax-deduction or rideshare logs next to the fuel log.

Best free gas mileage app: the free versions side by side

Five of the six apps are free to download, and what the free version leaves out is what separates them. Road Trip MPG is the exception: it is paid up front with nothing to buy afterwards. The table lists what each developer says about its free and paid tiers; prices are not listed because they vary by plan and storefront, so check the purchase screen.

Sources: the App Store listings and FAQs linked above, checked October 26, 2026.

Why is my app's MPG different from the EPA sticker?

A gas mileage app shows what your car actually does, and that rarely matches the window sticker. fueleconomy.gov's page Your Mileage Will Vary says EPA ratings "may not accurately predict the average MPG you will get" and lists the reasons: how and where you drive, the condition and maintenance of the vehicle, fuel variations, differences between vehicles of the same model, and engine break-in.

The label is already adjusted for the real world. The fueleconomy.gov FAQ says EPA reduces fuel economy test values by about 10% to account for ethanol in gasoline, wind, hills and road conditions. A log of your own fill-ups over several tanks is the figure to compare against, and our guide to improving gas mileage covers what moves it.

How to choose a gas mileage app: six questions

The right app is the one you will keep using at every fill-up, so start from how you live with your car.

• Do you want an account? Drivvo requires one and gives you the web; Fuelio and WrenchTime work without an account of their own, and Road Trip MPG describes none.
• Which phones are in the household? Drivvo and Fuelio run on Android and iPhone; Road Trip MPG and WrenchTime are for Apple devices.
• Do you sometimes fill up partially? Pick an app that says how it handles partial and missed fill-ups, or your MPG for that interval will be wrong.
• Subscription or one-time? Road Trip MPG is paid once up front with nothing to buy after; the others are free to download, and some also offer one-time upgrades, so check the purchase screen.
• Fuel only, or the whole car? Simply Auto adds trips and tax logs, WrenchTime adds trips that record themselves and OBD-II.
• How much do you want to type? Fuelio Pro adds offline receipt scanning; WrenchTime Pro reads a pump display or a receipt on the device and asks you to confirm before saving.

Key takeaways

The best gas mileage app, in eight points.

• Choose by need Fuelio for a free log with no account, Drivvo for the web, WrenchTime for a camera that reads the pump and for the whole car in one native iOS 26 app, Road Trip MPG for one payment, Fuelly for its website, Simply Auto for tax logs.
• Scan instead of typing of the apps on this page, WrenchTime is the one that reads the pump's LED display as well as the receipt, on the device and with Pro; the only other scanning cited is Fuelio's paid tier's on-device receipt scanning.
• Past the fuel log of the six, WrenchTime is the one that also reads the engine over OBD-II and logs a fill-up from an Apple Watch (Pro); the other five pages mention neither.
• MPG needs full fill-ups fueleconomy.gov divides miles since the last fill-up by the gallons to refill, over two complete fill-ups in a row.
• No account Fuelio's listing says no account is required; Road Trip MPG syncs through iCloud or Dropbox; WrenchTime uses your own iCloud.
• Cross-platform Drivvo runs on Android, iOS and the web, with an account and a free plan for up to 2 vehicles.
• One-time purchase Road Trip MPG has no in-app purchases and averaged 4.9 from 629 ratings on October 26, 2026.
• The label is not your number EPA lowers its test values by about 10%, and driving, maintenance and fuel still move real MPG.

Move your fuel log over and keep it honest

If you already have years of fill-ups in another app, import your history from Fuelly, Drivvo or Fuelio with WrenchTime Pro, full-tank and missed fill-up flags included, and read how the fuel economy tracker keeps tank-to-tank MPG right. With Pro, every new fill-up can come straight from the pump display or the receipt. The free version covers 1 vehicle and 3 fill-ups a month, with no ads.