xearno.tools

99 tools · tested math · operator benchmarks

The rules changed.
Most answers didn’t.

A bench of calculators kept current against rules that keep moving — tax, severance, residency, benefits, platform fees. Every tool computes today’s number, then reads it the way an experienced operator would: benchmarks, red flags, the formula in the open. Built for people and for AI agents — same tools, same math, callable over API and MCP.

From the makers of Xearno, the app that treats your money as a living fortune rather than a spreadsheet. And because we make an app — not loans, cards, or leads — there are no ads here, no affiliate offers, and no reason for any number to steer you anywhere.

Browse all toolsPoint your agent here

Not selling you a loan

Most calculator sites are lead-gen for lenders and advisors — the math frames the offer. We make an app, so the math has no side.

Formulas in the open

Every tool publishes its formula, assumptions, data basis, and what it deliberately excludes. Tested against worked examples; no silent changes.

A number, then a read

Results come with the benchmark and the trap — the sentence an experienced operator would add after the figure.

Half our users are not human

Language models reason well and compute badly. Every tool here is a pure, deterministic, versioned function with a published JSON schema — an agent calls it instead of doing the arithmetic in its head, and gets back the values and the benchmark read to show its user.

  • POST /api/v1/tools/:slug — open JSON API, no key needed
  • /mcp — mount the whole bench as MCP tools
  • /llms.txt — the map, readable by anything
curl -s https://xearno.tools/api/v1/tools/unit-economics \
  -H 'content-type: application/json' \
  -d '{"arpu": 50, "grossMargin": 80, "churn": 3, "cac": 400}'

{
  "raw": { "ltvCacRatio": 3.3, "paybackMonths": 10, ... },
  "insights": [
    { "level": "good",
      "text": "3.3:1 sits in the healthy 3–5:1 range..." }
  ]
}