Calculator API
Every Toolertools calculator is also a free JSON endpoint — the exact same engine that powers the page, so the numbers always match. No API key, no signup, CORS enabled. Results are planning estimates; each calculator page documents the formula, assumptions, and sources behind its numbers.
- OpenAPI 3.1 description (v1.0.0) — full request/response schemas
- API catalog (RFC 9727) for automated discovery
- Health check
Quick start
POST a JSON body to /api/v1/{tool}. A GET on the
same URL returns the tool's request schema and an example.
curl -X POST https://toolertools.com/api/v1/gravel \
-H 'Content-Type: application/json' \
-d '{"unitSystem":"imperial","length":20,"width":10,"depth":3,"gravelType":"crushed-stone","pricePerTon":45}'
Successful responses are { ok: true, tool, result, warnings }; invalid
input returns HTTP 422 with { ok: false, tool, errors } naming each problem
field.
Endpoints
| Endpoint | What it estimates | Calculator page |
|---|---|---|
/api/v1/gravel | Gravel volume, weight, and cost | gravel-calculator |
/api/v1/asphalt | Hot-mix asphalt tonnage and cost | asphalt-calculator |
/api/v1/concrete | Concrete volume, bags, and cost | concrete-calculator |
/api/v1/mulch | Mulch bags, volume, and cost | mulch-calculator |
/api/v1/topsoil | Topsoil volume, weight, and cost | topsoil-calculator |
/api/v1/paint | Paint gallons for a room | paint-calculator |
/api/v1/drywall | Drywall sheets for a room | drywall-calculator |
/api/v1/fence | Fence posts, panels, pickets, and rails | fence-calculator |
/api/v1/roofing | Roofing squares and shingle bundles | roofing-calculator |
/api/v1/dumpster | Recommended dumpster size | dumpster-size-calculator |
/api/v1/yards-to-tons | Cubic yards ↔ tons for bulk materials | cubic-yards-to-tons-calculator |
/api/v1/overtime | Overtime pay and weekly earnings | overtime-calculator |
/api/v1/hourly-to-salary | Hourly wage to annual salary | hourly-to-salary-calculator |
/api/v1/salary-to-hourly | Annual salary to hourly rate | salary-to-hourly-calculator |
/api/v1/commission | Sales commission, flat or tiered | commission-calculator |
/api/v1/commission-split | Real estate commission split | commission-split-calculator |
/api/v1/raise | New pay after a raise | raise-calculator |
/api/v1/bonus | Bonus take-home after withholding | bonus-calculator |
/api/v1/pto-accrual | PTO accrual and projected balance | pto-accrual-calculator |
/api/v1/pto-payout | Unused PTO payout | pto-payout-calculator |
/api/v1/freelancer-rate | Minimum freelance hourly rate | freelancer-hourly-rate-calculator |
Fair use
The API is free for reasonable automated use — agents, spreadsheets, scripts, and apps are all welcome. Please cache what you can and link back to the calculator page when you show results to people. There are no guarantees of uptime or stability yet; breaking changes will bump the version path.