# Rwanda Payroll Calculator
A single-file web app that converts between the three salary figures used in Rwandan payroll. Enter **any one** of them and it computes the other two:
- **Employer Gross** — total cost to the company (salary + employer contributions)
- **Employee Gross** — the contractual salary, i.e. the taxable base
- **Take-home Net** — what the employee actually receives
Unlike the usual spreadsheet approach (which only runs take-home → gross), this works in **all three directions**, including the reverse calculation through the progressive tax bands.
## Features
- Any-to-any conversion between the three amounts
- Click any result card to recalculate from that value
- Full two-sided breakdown (employee deductions vs. employer contributions)
- RWF and EUR display with an editable exchange rate
- Input validation, live thousands separators, decimal support
- Copy to clipboard, CSV export, print / save-as-PDF
- Light and dark mode
- Mobile-first responsive layout with a drawer menu
- Back/forward navigation via hash routing
- Runs entirely in the browser — no server, no data leaves the device
## Usage
Open `index.html` in any browser. No build step, no dependencies.
If served via GitHub Pages, it's live at `https:// .github.io/ /`.
## The calculation
Rates below are for **tax year 2025**.
### Contributions
| Contribution | Employee | Employer |
|---|---|---|
| RSSB Pension | 6% | 8% |
| RSSB Maternity | 0.3% | 0.3% |
| CBHI (medical) | 0.5% of net pay | — |
| PAYE (income tax) | progressive | — |
### PAYE bands (monthly, RWF)
| Taxable income | Rate |
|---|---|
| 0 – 60,000 | 0% |
| 60,001 – 100,000 | 10% |
| 100,001 – 200,000 | 20% |
| Above 200,000 | 30% |
### Formulas
Let `x` = employee gross (taxable amount).
```
Employer Gross = x × 1.083 (x + 8% pension + 0.3% maternity)
Net Pay = x − 0.06x − 0.003x − PAYE(x)
Take-home Net = Net Pay × 0.995 (less 0.5% CBHI)
```
Reversing take-home → gross inverts the piecewise …