Estimate a horse-racing return after a Rule 4 deduction is applied to winnings, while keeping the returned stake separate.
Adjusted winnings = stake × (decimal odds − 1) × (1 − deduction ÷ 100); total return = stake + adjusted winnings.
The calculator runs entirely in your browser and sends no betting data to a server.
The default fields provide a worked example. Press Calculate to recompute every displayed value from those inputs; changing any input marks the result for an update.
| Check | Meaning |
|---|---|
| Main result | Adjusted total return |
| Precision | Full precision internally; sensible display rounding |
This tool applies the formula shown above to the supplied numbers. It does not retrieve live odds or predict an outcome. Market settlement, deductions, commissions, voids, and rounding can differ by operator and jurisdiction.
Use the result as an audit aid and check the market’s official rules before relying on it.
It uses only the values shown in the calculator. Enter decimal odds and monetary amounts in consistent units where applicable.
Adjusted winnings = stake × (decimal odds − 1) × (1 − deduction ÷ 100); total return = stake + adjusted winnings. Intermediate values retain full JavaScript precision and displayed figures are rounded.
The calculator rounds only for display. A bookmaker may round at a different stage, so a small account-level difference is possible.
Yes. Voids, dead heats, commission tiers, deductions, overtime and market-specific settlement can differ. Check the rules attached to the actual market.
No. It is a transparent mathematical estimate from the entered assumptions and does not predict events or guarantee a return.
| Item | Rule |
|---|---|
| Odds | Decimal format |
| Rounding | Display stage only |
| Data | Processed locally |