About MaCalculatriceEnLigne
macalc is an MCP server for everyday calculations, with a curated core of 15 tools and discovery-based access to a catalog of 446 calculators. It serves people who need calculations across finance, health, math, construction, and other categories, without an API key.
Key features
- 0115-tool curated core profile
- 02Discovery and dispatch for 446 calculators
- 03Calculators across eight countries' tax systems
- 04Remote HTTP and local stdio options
- 05Structured JSON with formulas and sources
Use cases
- 01Estimating income tax or net salary
- 02Calculating mortgage payments and interest
- 03Finding a calculator beyond the default tool set
MCP support
macalc exposes calculator tools to MCP clients over a remote Streamable HTTP endpoint or a local stdio proxy. The default local profile has 15 tools, while the full catalog is available remotely or through discovery and dispatch.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://macalculatriceenligne.com/api/mcpclaude mcp add --transport http tresor4k-macalc https://macalculatriceenligne.com/api/mcp{"mcpServers":{"tresor4k-macalc":{"type":"http","url":"https://macalculatriceenligne.com/api/mcp"}}}Open in Cursor{"servers":{"tresor4k-macalc":{"type":"http","url":"https://macalculatriceenligne.com/api/mcp"}}}Open in VS Code{"mcpServers":{"tresor4k-macalc":{"type":"http","url":"https://macalculatriceenligne.com/api/mcp"}}}{"mcpServers":{"tresor4k-macalc":{"serverUrl":"https://macalculatriceenligne.com/api/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
446| Parameter | Type | Required | Description |
|---|---|---|---|
| _unused | string | No | No parameters needed |
Details
From the project READMEmacalc — Everyday Calculator MCP Server
A curated core of 15 well-scoped calculator tools — income tax (France, US, UK, Canada), gross-to-net salary, mortgage, compound interest, loans, VAT, percentages, BMI, TDEE — with on-demand access to the full macalc catalog of 446 calculators (22 categories, 8 countries' tax systems) through a discovery + dispatcher workflow. Free, no API key required.
Core tools (default profile)
| Tool | What it does |
|---|---|
calculate_french_income_tax | French income tax 2026 (Article 197 CGI, family quotient) |
calculate_french_salary | French gross → net salary 2026 (cadre / non-cadre / civil servant) |
calculate_us_federal_tax | US federal income tax 2026 (IRS brackets + standard deduction) |
calculate_uk_income_tax | UK income tax 2025/26 (HMRC bands, allowance taper) |
calculate_canada_federal_tax | Canadian federal income tax (CRA brackets + BPA) |
calculate_mortgage | Monthly payment, total interest, amortization schedule |
calculate_compound_interest | Lump-sum compound growth with yearly breakdown |
calculate_loan_payment | Generic amortizing loan (term in months) |
calculate_percentage | Percent of total / percent change / what-percent |
calculate_vat_generic | Add or remove VAT/GST/sales tax at any rate |
calculate_bmi | Body Mass Index + WHO category |
calculate_tdee | Maintenance calories from BMR + activity level |
list_bundles | Discover the 31 thematic bundles of the full catalog |
get_bundle_tools | List the tools inside one bundle |
call_any_calculator | Invoke any of the 446 hosted calculators by name |
Need something not in the core (notary fees, concrete volume, VMA, pet food…)? list_bundles → get_bundle_tools(bundle_id) → call_any_calculator(tool_name, arguments).
Prefer the raw 446-tool listing? Set the env var MACALC_MCP_FULL=1.
Quick Start
Two install modes — pick whichever your MCP client supports.
Option A — Remote (Streamable HTTP, zero install)
For clients with native remote MCP support (Claude Desktop ≥ 0.8, Cursor, Windsurf, VS Code MCP, etc.)
{
"mcpServers": {
"macalc": {
"url": "https://macalculatriceenligne.com/api/mcp"
}
}
}
Option B — Local stdio proxy (works everywhere)
For clients that only speak stdio, or sandboxed environments:
{
"mcpServers": {
"macalc": {
"command": "npx",
"args": ["-y", "macalc-mcp"]
}
}
}
Or with Docker (tresor4k/macalc-mcp on Docker Hub):
{
"mcpServers": {
"macalc": {
"command": "docker",
"args": ["run", "-i", "--rm", "tresor4k/macalc-mcp"]
}
}
}
That's it. No API key, no auth, no setup.
Note: Option A (remote URL) serves the full 446-tool catalog directly. Option B (this npm wrapper) serves the curated 15-tool core profile by default — lighter on your agent's context window — with the full catalog one dispatcher call away.
What's Inside — The Full Catalog
Finance (8 countries)
| Country | Tools | Examples |
|---|---|---|
| 🇫🇷 France | 85+ | Income tax (IR 2026), salary gross→net, VAT, mortgage, notary fees, inheritance, retirement, unemployment, auto-entrepreneur |
| 🇧🇪 Belgium | 35+ | Precompte professionnel, bonus emploi, pension, cheques repas, droits donation |
| 🇨🇭 Switzerland | 30+ | Federal + cantonal tax, AVS/LPP, LAMal, 3rd pillar, frontalier |
| 🇨🇦 Canada/Quebec | 25+ | Federal + provincial tax, RRQ, RQAP, REER, CELI, TPS/TVQ |
| 🇺🇸 USA | 15+ | Federal income tax, FICA, state tax, 401k, HSA |
| 🇬🇧 UK | 10+ | Income tax, NI, SDLT, student loan repayment |
| 🇲🇦 Morocco | 10+ | IR, CNSS, TVA |
| 🇸🇳 Senegal | 10+ | IR, CSS, TVA |
Health & Sport (50+ tools)
BMI, BMR (Mifflin/Harris-Benedict), TDEE, heart rate zones (Karvonen), 1RM (Epley/Brzycki), VMA (Cooper/Luc-Léger), VO2max, race prediction (Riegel), marathon/half pace, due date (3 methods), ovulation calendar, body fat (Navy method), daily calories, macros, hydration.
Math (60+ tools)
Percentages (increase/decrease/ratio), averages (weighted/geometric/harmonic), Pythagoras, area (triangle/circle/rectangle/trapezoid/polygon), volume (sphere/cylinder/cone/cube), perimeter, equations (1st/2nd degree), sequences (arithmetic/geometric), fractions, statistics (mean/median/mode/std dev), GCD/LCM, base conversion.
Construction (40+ tools)
Concrete volume & mix (B25 DTU 21), paint coverage, tile quantity, staircase dimensions (Blondel formula), insulation R-value, roof surface & slope, cable section (NF C 15-100), beam dimensioning (Eurocode 5), gravel/sand tonnage, wallpaper rolls, plasterboard sheets.
Science (25+ tools)
Ohm's law, Newton's laws, pH calculation, dilution (C1V1=C2V2), density, radioactive decay, speed of sound, ideal gas law, molar mass, concentration.
Conversions (40+ tools)
Temperature, distance, weight, volume, speed, pressure, energy, data storage, cooking units, shoe sizes, clothing sizes, currency.
Running & Cycling (35+ tools)
Pace calculator, VMA (6 test methods), VO2max, FTP, heart rate zones, race prediction, training plan, calorie burn, hydration needs, bike gear ratio, tire pressure.
Education (20+ tools)
GPA calculator (French bac/brevet system), weighted average, statistics, derivatives, combinatorics, probability distributions.
Real Estate (15+ tools)
Rental yield (gross/net/net-net), Pinel tax reduction, PTZ eligibility, DPE energy class, Carrez surface, notary fees by department, loan comparison.
Cooking & Nutrition (15+ tools)
Recipe nutrition calculator, baking conversions, glycemic load, caffeine intake, daily vitamins, unit conversions (cups/ml/oz).
Travel (10+ tools)
Luggage weight calculator, jet lag recovery, travel budget, voltage adapters, sun exposure time.
Animals (8+ tools)
Dog/cat food calculator, pet age converter (corrected formula), aquarium volume, breeding due date.
Astronomy (8+ tools)
Sunrise/sunset, moon phase, solar panel output, wind chill, heat index, carbon sequestration.
Textile (5+ tools)
Fabric yardage, knitting yarn calculator, ring/bra/hat size converters.
Exemples d'outils
- Impôt sur le revenu : page web du calculateur correspondant à l'outil
calculate_french_income_tax(barème IR 2026, quotient familial). - Salaire brut en net : page web du calculateur correspondant à l'outil
calculate_french_salary(cadre, non-cadre, fonction publique). - Mensualité de prêt immobilier : page web du calculateur correspondant à l'outil
calculate_mortgage(mensualité, intérêts totaux, tableau d'amortissement).
Technical Details
| Property | Value |
|---|---|
| Endpoint | https://macalculatriceenligne.com/api/mcp |
| Transport | Streamable HTTP (stateless) |
| Protocol | MCP v1 (@modelcontextprotocol/sdk ^1.27.1) |
| Auth | None (free, no API key) |
| Rate limit | 1,000 calls/day |
| Response format | Structured JSON with formula, source, reference URL |
| Discovery | https://macalculatriceenligne.com/.well-known/mcp/server.json |
Example Usage
Ask your AI assistant:
"Calculate the French income tax on 45,000€ for a single person"
The assistant calls calculate_french_income_tax with {income: 45000, parts: 1} and returns:
{
"impot": 4611,
"taux_effectif": "10.2%",
"taux_marginal": "30%",
"tranches": [
{"min": 0, "max": 11624, "taux": "0%", "impot": 0},
{"min": 11624, "max": 29638, "taux": "11%", "impot": 1982},
{"min": 29638, "max": 45000, "taux": "30%", "impot": 2629}
],
"source": "Article 197 CGI — Loi de finances 2026",
"reference_url": "https://macalculatriceenligne.com/finance/fiscalite/calcul-impots/"
}
All Tool Categories
Finance FR (85) Finance BE (35) Finance CH (30)
Finance CA (25) Finance US (15) Finance UK (10)
Finance MA (10) Finance SN (10) Health (30)
Sport/Running (35) Math (60) Construction (40)
Science (25) Conversions (40) Education (20)
Real Estate (15) Cooking (15) Travel (10)
Animals (8) Astronomy (8) Textile (5)
Automotive (10)
Total: 446 tools (hosted catalog — counts per category are approximate)
Links
- Website: macalculatriceenligne.com
- MCP endpoint: macalculatriceenligne.com/api/mcp
- MCP info page: macalculatriceenligne.com/mcp/
- API docs: macalculatriceenligne.com/api-docs/
- Chrome extension: Calculer Partout
- Telegram bot: @macalculatrice_bot
License
MIT
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.