Split Bill Calculator
Even shares with tax and tip for restaurant bills.
What it does
Restaurant checks stack three layers: food subtotal, sales tax on it, and tip by custom on the pre tax amount. Splitting evenly means adding all three first, then dividing once.
The tool above takes subtotal, tax rate, tip rate, and head count. It returns the table total, each even share, and the combined tax plus tip.
Tip base customs vary by table. Pre tax tipping is the classic norm and slightly lower; post tax tipping is simpler from the receipt total. Agree before calculating and the argument never starts.
Uneven tables break even splits. When orders differ wildly, run each diner subtotal through the same math separately instead of averaging lobster with salad.
How to use
- Enter the food subtotal before tax and tip.
- Enter the receipt tax rate.
- Enter the agreed tip rate.
- Divide by head count and round shares up slightly.
Formula
- subtotal
- Food and drinks base for both add ons.
- tax rate
- Combined local rate from the receipt.
- tip rate
- Agreed percent on the pre tax base.
Post tax tipping swaps the tip base to subtotal plus tax. The gap runs about the tax rate times the tip rate, near 1.5% of the bill here.
Worked example
Example: $120, 8.5% tax, 18% tip, 3 people
Subtotal 120, tax 8.5%, tip 18%, three diners.
- Tax: 120 x 0.085 = $10.20.
- Tip: 120 x 0.18 = $21.60.
- Tax plus tip: 10.20 + 21.60 = $31.80.
- Total: 120 + 31.80 = $151.80.
- Each: 151.80 / 3 = $50.60.
Reference table
| Tip | 2 people | 3 people | 4 people |
|---|---|---|---|
| 15% | $92.25 | $61.50 | $46.13 |
| 18% | $94.50 | $63.00 | $47.25 |
| 20% | $96.00 | $64.00 | $48.00 |
Limits
- Even shares assumed. Uneven orders need separate runs.
- Pre tax tip base assumed.
- Auto gratuities need checking before adding more.
- Cash rounding can miss the total by cents.
Common mistakes
- Tipping on the taxed total without agreeing first.
- Splitting before adding tax and tip.
- Missing the automatic large party charge.
- Rounding each share down below the total.
- Averaging wildly unequal orders.
Try it yourself
Quick checks. Answers sit tucked under each question.
$90 subtotal, 10% tax, 20% tip, 2 people?
Tax 9, tip 18, total 117. Each pays $58.50.
Same bill, 3 people?
117 / 3 = $39.00 each.
Questions
Tip before or after tax?
Pre tax is classic. Agree first; the gap is small either way.
How do we split uneven orders?
Run each subtotal separately with shared items divided, then add.
What about the wine one person drank?
Personal items stay personal. Split only genuinely shared plates.
Should shares round up?
Yes slightly. Rounding down collects short of the total.
Who pays the auto gratuity?
Everyone proportionally. Check the receipt so it is not tipped twice.
Cash or card for splits?
Card per person when accepted. Cash needs one collector doing this math.