Bill Splitter & Weighted Split Warikan · omikuji tools

✨ Features

  • Instant per-person amount from just the total and headcount. Even split in one tap.
  • Weighted splitting with per-group multipliers or fixed amounts for boss, senior, junior, etc.
  • Rounding by ¥1–¥500 (floor/ceil/round) with automatic surplus/shortfall display.
  • Remainder roulette to decide who absorbs the leftover, plus QR/URL sharing of the setup.

🪄 Use cases

Party organizer

Enter total and headcount to show the per-person amount instantly. Round down and let the organizer cover the rest in one tap.

Tilted dinners

Charge seniors more and juniors less by setting per-group multipliers or fixed amounts for a fair share.

Trip & event settlement

Share the result by URL or QR. When the other person opens it, the same breakdown is restored.

Assigning the remainder

When there's surplus or shortfall, the remainder roulette picks who handles it — with a fun reveal.

🔒 Privacy

All calculation happens entirely in your browser. Amounts, headcounts and other data are never sent to a server. The shared-link state is encoded in the URL and not stored on any server.

❓ FAQ

How do I choose the weighting multipliers?

Use juniors as the ×1 baseline, then set seniors to ×1.5, the boss to ×2, and so on as relative values. Switch a group to fixed mode to set an exact amount like 'just this person pays 3000'.

What is the rounding unit?

It's the unit each person's amount is rounded to: ¥1, ¥10, ¥100 or ¥500. Rounding up to ¥100 makes collecting cash easier.

Can I send the result to someone?

Use 'Share / QR' to generate a short URL and QR code. Opening the link restores the total, headcount, group setup and rounding settings exactly.

Is the remainder roulette fair?

It picks the winner with the browser's cryptographic randomness (crypto.getRandomValues), so everyone has equal odds. Participant names are fully editable.
1Bill
Bill
Total amount due Total
¥
Split mode Mode
People People
4ppl
Split evenly among everyone
2Rounding
Rounding
Rounding unit Unit
Method Method
Even split · RESULT
Per person
¥0
—
Collected
¥0
Total
¥0
Difference
¥0
Enter an amount to see the result.