An app for fairly splitting fuel cost, expressway tolls, and parking fees when you travel somewhere by car with others. Works on your phone.
warikan-drive.pages.devIn the new itinerary UI, you can set the distance and riders separately for outbound and return. Even for a round trip, you can settle up separately for someone who only joins on the way back.
You can select more than one driver. Choose one person from the participants as the car provider, and set consideration for driving and consideration for providing the car separately. "Reduce burden" lowers that person's own share; "Thank-you" is an amount that person receives.
The free version doesn't use a route-search API. Calculations, history, cars, and spots are stored on your device.
Google Maps and expressway operators' toll search only open as an external site when you tap the button. Any toll you enter is saved to your own history for reuse.
Use A− / A＋ at the top of this guide to change the text size across 4 steps: 16, 18, 21, or 24px. The default is 16px, and your chosen size is saved in this browser. If it can't be saved, you can still change it while this page stays open.
Amounts and names are never sent anywhere. That's why there's no sign-up and no password — open it and use it right away.
Once you've opened it, it keeps working even deep in the mountains. You can calculate and check past records with no connection at all.
If you close the screen in the middle of entering something, it picks up right where you left off next time. There's no "forgot to save it" problem.
Opening a browser every time is a hassle, so add it to your home screen once at the start. It gets its own icon, just like a regular app.
If it worked, the address bar disappears and the app runs full-screen. From here on, just open it.
The screen runs top to bottom in a single path. Just fill it in from the top, and the answer appears at the bottom. Feel free to skip anything you're not sure about.
Write something like Hakusan climb in the top field. It's a handy label when you look back at your records later.
Enter Starting point and Destination. Rough names like "Osaka" or "Hakusan, Ichinose" are fine.
Choosing Round trip automatically doubles the distance. If you're coming back in the same car, leave it on round trip.
Enter a number for One-way distance. Just use the figure from your car's navigation system or a map app.
If you'd rather enter the actual distance measured on your car's odometer after you get back, switch to Enter total distance.
Use − and ＋ to change the number of people. The total is divided by this number.
Enter the toll amount. You can enter outbound and return separately. Handy when the route differs each way, or you only used the expressway one way.
Tap + Add expressway toll to add as many as you like. You can also enter a toll road along the way as a separate item.
Choose from four methods. Just pick whichever is easiest for you.
| Method | What you enter | Best for |
|---|---|---|
| From fuel economy | Fuel economy, fuel price | Most accurate — when you know your car's fuel economy (km/L) |
| Cost per km | Amount per km | Handy if you've already decided on something like "¥15/km" |
| Amount refueled | The actual amount you paid | After the trip, working from a receipt |
| Rough estimate | A rough amount | When "about ¥8,000" is good enough |
Not sure? Cost per km is the easiest. As a guideline, a regular car runs around ¥15/km; a kei car (Japan's small light-vehicle class) runs about ¥10–12/km.
Add as many as you like with + Add parking and + Add expense. You can name each item anything you like.
Ferries, toll tunnels, car washes, pay-and-display parking... add anything you spent money on.
The amount per person appears in large text on the green card at the bottom. There's no calculate button — it's calculated automatically every time you enter something.
About rounding. Amounts are rounded to the nearest ¥1, ¥10, or ¥100, and any remainder that doesn't divide evenly is assigned to one person, labeled "rounding adjustment." Everyone's shares always add up to the total cost, and the amount owed matches the amount transferred. To switch to rounding by ¥10 or ¥100, use Calculation settings at the bottom.
Creates text you can paste straight into LINE or an email. It includes the cost breakdown and the amount per person.
It's added to History in the menu below. Next time you go to the same place, tap Run again with these settings to carry over the distance and number of people and calculate fresh.
Switching between Quick, Detailed, and Actual costs at the top of the screen changes how many fields show up.
Switching never erases anything you've entered. Only the number of visible fields changes, so feel free to switch back and forth.
From the menu below, go to My cars → Register a car → Choose by model.
Type the car's name to search, and fuel economy fills in automatically. You can search using Japanese kana too (even "purius" finds the Prius). This uses fuel-economy data published by Japan's Ministry of Land, Infrastructure, Transport and Tourism.
It wouldn't be fair to charge someone who got in partway, at Otsu, the same amount as someone who rode all the way from Osaka. This is for cases like that.
Switch to Detailed, then choose By leg under How to split costs. Enter the distance and who was riding for each leg, and each person only pays for the legs they were actually on.
Fuel cost and expressway tolls are split by leg, while parking is shared equally by everyone, since it's used by the whole group at the destination.
Under Thank-you for the driver, choose Driver allowance.
You can set it as "¥3,000 total" or "¥500 per person." Passengers pay a bit more and the driver's own share drops by that amount. This is kept separate from the trip expenses, so the driver never ends up paying part of their own thank-you.
In Detailed mode, each item gets a Paid by: ___ field. Once you've set who covered each expense, Who pays whom? shows the full list of transfers needed.
If you skip this, you can still settle up simply by collecting ¥___ from each person.
What you entered before setting off was "roughly this much." Let's update it to what you actually paid.
Each item gets an extra actual cost field. Whatever you enter there is used instead of the estimate for the calculation.
| Estimate | Actual | Used in calculation | |
|---|---|---|---|
| Expressway tolls | ¥12,800 | ¥12,340 | ¥12,340 |
| Fuel | ¥8,700 | ¥8,240 | ¥8,240 |
Estimates and actual costs are shown in different colors and text, so you can tell at a glance which figure is being used.
In the free version, you enter distance and expressway tolls yourself. You can record figures you look up on Google Maps, or on an expressway operator's official toll search.
Google Maps and the toll search site only open when you tap the button. Nothing you enter is sent anywhere else when you save.
The "Expressway toll search" button opens the official search run by NEXCO West Japan (a Japanese expressway operator). It also covers routes outside western Japan and the Honshu–Shikoku bridge links, but some roads and discounts aren't included. Any interchange or date/time you entered in the app isn't carried over to that site automatically.
Roads not covered by the search ↗
For any toll cost the search results don't cover, if everyone shares it, add it under "Other expenses" with the road's name. Enter a round-trip toll only once, and watch out for counting it twice.
If different people rode outbound versus on the way back, add the cost to the matching direction under "Expressway tolls." In older drafts, turning off "Use registered spots / separate outbound and return entry" lets you set riders separately for each direction.
The list may sometimes show outdated information. Check each road operator's own site for the latest tolls and any toll-free changes.
Tolls shown are either estimates or entered by hand. If you have an actual ETC statement or receipt, use that actual figure instead. Official search tolls can also vary by vehicle type, ETC status, time of day, and discount conditions.
No automatic-lookup code is used. As long as you enter distance and tolls by hand, everything else — calculations, history, sharing, and so on — works exactly the same.
Fuel economy, fuel price, or distance is blank. The screen should show "⚠️ ___ hasn't been entered" — fill in that field.
An "actual cost" may still be set from earlier. When an actual cost is entered, it takes priority over the estimate.
In that case you'll see a message like "Actual cost ¥___ already entered." Switch to Actual costs to check or change it.
It's fine to type with Japanese input (kana) still switched on. Even full-width digits like "１２００" are automatically converted to "1200."
Records are stored on your phone. Clearing your browser's "browsing data" deletes them too.
Also, opening the app in a different browser or in private/incognito mode is treated as a separate place, so your records won't show up there.
Tap New calculation in the top right. Whatever you were entering is cleared and you start from a blank slate. (Saved history is not deleted.)
Some things are quicker to understand by trying them than by reading about them. Come back here anytime if you get stuck.
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