The honest yearly cost of running open-source software yourself, set against the bill it replaces, with the seat count where it stops paying.
Arithmetic only — not tax, accounting, legal or investment advice. Check against current rules.
Self-hosting vs SaaS cost: The yearly cost is hosting, backups and tooling, plus admin and restore-test hours at the hourly rate the reader enters. Break-even seats is that cost over the vendor's yearly price per seat.
Quoted from the toolbelt spec, the document this tool was built against.
Negatives are parenthesized because that’s what a statement does. The rest is four promises.
Amounts are integers in the currency's smallest unit, end to end. A float never touches a cent.
Rounded once, at the end. Rounding each operand is how a split stops summing to the whole.
The arithmetic lives in one unit-tested module, and the extension uses the same one.
There is no request to make. What you type stays in this tab and is gone when you close it.
A calculator answers the question once. These carry the answer into a product, name what it computed, and argue the method.
Worked example. Type over it.
Result
| Self-hosting, per year | Amount |
|---|---|
| Hosting, backups, tooling | 720.00 |
| Admin and restore-test time | 2,640.00 |
| Total | 3,360.00 |
| One-off set-up (not in the yearly total) | 1,200.00 |
The saving holds only if the time is real. Price the admin hours at what that person's time costs the company, not at zero.