Numveo
Free · no key required (rate-limited)

Developers — API & Embed

Use 150 calculators in your own product. The API runs the exact same engine and pinned formula versions as this site, so results always match — down to the last cent.

Base URL & limits

All endpoints live under /api/v1. CORS is open, and requests are rate-limited to 60 per minute per IP (a 429 with Retry-After when exceeded). No key is required today; API keys & quotas arrive with higher tiers.

GET/api/v1/calculators

The full catalogue with each calculator's input and result schemas.

curl https://numveo.com/api/v1/calculators
GET/api/v1/calculators/{slug}

A single calculator's definition (inputs, results, metadata).

curl https://numveo.com/api/v1/calculators/mortgage-calculator
POST/api/v1/calculate

Run a calculation. Pass the slug and an inputs object; optionally pin a formula version. Returns values, a formatted view, and any breakdown / schedule.

curl -X POST https://numveo.com/api/v1/calculate \
  -H "Content-Type: application/json" \
  -d '{
    "slug": "mortgage-calculator",
    "inputs": { "loanAmount": 400000, "interestRate": 6.5, "termYears": 30 }
  }'
{
  "slug": "mortgage-calculator",
  "formulaKey": "mortgage_payment",
  "formulaVersion": 2,
  "values": { "monthlyPayment": 3178.27, "principalAndInterest": 2528.27, ... },
  "formatted": { "monthlyPayment": "$3,178.27", ... },
  "breakdown": [ { "label": "Principal & interest", "value": 2528.27 }, ... ]
}
GET/api/v1/articles
GET/api/v1/articles/{slug}

The knowledge base: guides and glossary terms. Filter the list with ?section=guide or ?section=glossary.

curl "https://numveo.com/api/v1/articles?section=glossary"

Embeddable widgets

Drop any calculator into your page with an iframe — no JavaScript, no key. The widget renders chrome-free and computes entirely in the visitor's browser.

<iframe
  src="https://numveo.com/embed/mortgage-calculator"
  width="100%" height="640" style="border:0" loading="lazy"
  title="Mortgage Calculator"></iframe>

You'll find a ready-to-copy snippet on every calculator page.