French Payroll, Tax & Legal Calculators for AI Agents

Exact French calculations that language models usually get wrong, as a tool your AI agent can call: salary gross to net and back, income tax 2026, notary fees, severance and conventional termination pay, retirement indemnity, fixed-term contract bonus, mileage allowance, VAT, car registration cost, ecological malus, full cost of importing a car, driving licence points recovery.

Every result comes with the official sources (Légifrance, service-public.gouv.fr, URSSAF, impots.gouv.fr), the date the rules were checked, and a link to a page that explains the calculation in French on calculons.fr, where the same engines run for thousands of people each day.

Why use it

• Deterministic and sourced. Same input, same output, rules of 2026 written as code, not guessed by a model.
• Built for agents. One input, one JSON result with a one-line summary. If a parameter is missing or wrong, the result says which fields are expected and gives an example, so the agent can fix its call by itself.
• Errors are free. You only pay for successful calculations.
• Fast and light. No browser, no scraping, no external API: a run takes about a second.

How to call it

One calculation:

{
  "calculator": "severance-pay",
  "params": { "salaireMensuel": 3000, "ancienneteAnnees": 12, "ancienneteMois": 4 }
}

Several at once (up to 500, one charge per successful calculation):

{
  "calculations": [
    { "calculator": "salary-gross-to-net", "params": { "brutMensuel": 3200, "statut": "cadre", "tauxPas": 0.075 } },
    { "calculator": "notary-fees", "params": { "prix": 180000, "type": "neuf" } }
  ]
}

From an AI agent, call it through the Apify MCP server like any other Actor.

Output

{
  "calculator": "severance-pay",
  "ok": true,
  "params": { "salaireMensuel": 3000, "ancienneteAnnees": 12, "ancienneteMois": 4 },
  "summary": "Statutory severance pay 9,833.33 € for 12.33 years of service.",
  "result": { "indemniteLegale": 9833.33, "ancienneteTotaleAnnees": 12.33, "salaireReference": 3000, "aucuneIndemniteDue": false },
  "rules": {
    "verifiedOn": "2026 rules",
    "sources": ["https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000035644154"]
  },
  "page": "https://calculons.fr/calculateurs/indemnite-licenciement",
  "disclaimer": "Indicative calculation under French law ... not legal, tax or financial advice."
}

A wrong call (not charged):

{
  "calculator": "notary-fees",
  "ok": false,
  "error": "\"type\" must be one of: ancien, neuf",
  "expectedParams": ["prix: number, purchase price in euros", "type: \"ancien\" (existing property) | \"neuf\" (new build)"],
  "example": { "prix": 250000, "type": "ancien" }
}

Calculators

Field names are French, as in French payslips and forms. Amounts are in euros, dates are YYYY-MM-DD, a ? marks an optional field.

calculator	what it does	params	rules checked
salary-gross-to-net	French employee salary: monthly gross to net (before and after income tax withholding), with each employee contribution.	brutMensuel number, monthly gross salary in euros statut "non-cadre" or "cadre" or "public" tauxPas? number 0 to 0.45, income tax withholding rate (default 0) tempsPlein? boolean, full time (default true)	2026 rules
salary-net-to-gross	French employee salary: find the monthly gross salary that gives a target net (before tax, taxable, or after tax).	netMensuel number, target monthly net in euros statut "non-cadre" or "cadre" or "public" cible "avant-impot" (net before tax) or "imposable" (taxable net) or "apres-impot" (net after withholding) tauxPas? number 0 to 0.45, withholding rate, used only when cible = "apres-impot" (default 0)	2026 rules
income-tax	French income tax (impôt sur le revenu) 2026 on 2025 income: family quotient (parts), cap, discount (décote), average and marginal rates.	revenuNetImposable number, household net taxable income in euros (after the 10 % deduction) conjoint? boolean, married or civil partnership, joint taxation (default false) enfants? number, dependent children (default 0) enfantsHandicap? number, of which disabled children (default 0) parentIsole? boolean, single parent, box T (default false) invalidite? boolean, disability card, box P (default false)	2026 rules
notary-fees	French notary fees (frais de notaire) for buying a property: transfer taxes (DMTO), regulated fees, security contribution, disbursements.	prix number, purchase price in euros type "ancien" (existing property) or "neuf" (new build) dmtoRate? number, departmental transfer tax rate if not the standard one, e.g. 0.0632 (default: engine standard)	2026 rules
severance-pay	French statutory severance pay (indemnité légale de licenciement): 1/4 month per year up to 10 years, 1/3 beyond.	salaireMensuel number, reference gross monthly salary in euros ancienneteAnnees number, full years of service ancienneteMois? number 0 to 11, extra months of service (default 0) motif? "personnel" or "economique" (default "personnel")	2026 rules
conventional-termination	French conventional termination (rupture conventionnelle): statutory minimum indemnity.	salaireReference number, reference gross monthly salary in euros ancienneteAnnees number, full years of service ancienneteMois? number 0 to 11, extra months of service (default 0)	2026 rules
retirement-severance	French retirement indemnity (indemnité de départ ou de mise à la retraite): voluntary departure or retirement imposed by the employer.	salaireMensuel number, reference gross monthly salary in euros ancienneteAnnees number, full years of service ancienneteMois? number 0 to 11 (default 0) type "volontaire" (employee leaves) or "mise_a_la_retraite" (employer decides)	2026 rules
fixed-term-end-bonus	French end-of-contract bonus for a fixed-term or temp contract (prime de précarité, 10 % or 6 %), with indicative paid-leave allowance.	mode? "total" (give brutTotal) or "mensuel" (give salaireMensuel and dureeMois) (default "total") brutTotal? number, total gross pay of the contract (mode "total") salaireMensuel? number, monthly gross salary (mode "mensuel") dureeMois? number, contract length in months (mode "mensuel") taux? number, 0.1 (default) or 0.06 if a branch agreement provides training	2026 rules
mileage-allowance	French mileage allowance scale (barème kilométrique) for income tax real expenses or employer refunds.	km number, kilometres driven in the year cv number, fiscal horsepower (CV) typeVehicule? "voiture" or "moto" or "cyclomoteur" (default "voiture") electrique? boolean, electric vehicle, +20 % (default false)	2026 rules
vat	French VAT (TVA): excluding tax to including tax and back, at 20 %, 10 %, 5.5 %, 2.1 % or 0 %.	montant number, amount in euros taux number, 0.2 or 0.1 or 0.055 or 0.021 or 0 sens? "ht-vers-ttc" (excl. to incl. tax, default) or "ttc-vers-ht"	2026 rules
vehicle-registration-tax	French vehicle registration certificate cost (carte grise): regional tax per fiscal horsepower, fixed tax, delivery fee, malus.	regionId string, region of the owner's home: auvergne-rhone-alpes, bourgogne-franche-comte, bretagne, centre-val-de-loire, corse, grand-est, hauts-de-france, ile-de-france, normandie, nouvelle-aquitaine, occitanie, pays-de-la-loire, provence-alpes-cote-dazur, guadeloupe, martinique, guyane, la-reunion, mayotte chevauxFiscaux number, fiscal horsepower (box P.6) plus10ans? boolean, first registered more than 10 years ago, regional tax halved (default false) electrique? boolean, electric or hydrogen vehicle (default false) malus? number, ecological malus in euros for a first registration in France (default 0)	2026-10-19
ecological-malus	French ecological malus 2026 on new cars: CO2 malus (WLTP) and weight malus, with exemptions and family deduction.	co2 number, CO2 emissions in g/km (WLTP) masse number, mass in running order in kg energie "thermique" or "hybride" or "hybride_rechargeable" or "electrique" enfants? number, dependent children (deduction from 3) (default 0)	2026 rules
car-import-cost	Full cost of importing a car into France (EU or non-EU): VAT if new for tax purposes, customs duty, malus for imported used cars, registration certificate, fees.	provenance "ue" or "hors-ue" vendeur "particulier" (private seller) or "professionnel" (dealer) prix number, price paid in euros (excl. VAT for a car new for tax purposes bought in the EU) datePremiere date YYYY-MM-DD of first registration abroad, or "" if never registered dateFrance? date YYYY-MM-DD of registration in France (default today) kilometrage number, mileage in km energie "essence" or "diesel" or "gpl" or "e85" or "micro-hybride" or "hybride" or "hybride-rechargeable" or "electrique" co2 number, CO2 g/km (WLTP if available) masse number, mass in running order in kg chevauxFiscaux number, French fiscal horsepower regionId string, region of the owner's home: auvergne-rhone-alpes, bourgogne-franche-comte, bretagne, centre-val-de-loire, corse, grand-est, hauts-de-france, ile-de-france, normandie, nouvelle-aquitaine, occitanie, pays-de-la-loire, provence-alpes-cote-dazur, guadeloupe, martinique, guyane, la-reunion, mayotte droitsReduits? boolean, non-EU only: preferential origin proven, no 10 % duty (default false) transport? number, transport cost in euros (default 0) plaquesAssurance? number, temporary plates and insurance (default 0) coc? number, certificate of conformity (default 0) controleTechnique? number, roadworthiness test (default 0) fraisDossier? number, other administrative fees (default 0)	2026-10-25
driving-licence-points	French driving licence points: balance today, date when the 12 points come back, probationary licence, awareness courses.	probatoire? null for a full licence, or {dateObtention: "YYYY-MM-DD", aac: boolean (accompanied driving), formation: boolean (extra training)} (default null) infractions array of {date: "YYYY-MM-DD" (date the offence became final), points: number, categorie: "c1" or "c2" or "c3" or "c4" or "c5" or "delit", libelle: string} stages? array of "YYYY-MM-DD", first day of each awareness course (default []) aujourdhui? date YYYY-MM-DD used as today (default today)	2026-10-24

Pricing

Pay per event: $0.005 per successful calculation ($5 per 1,000), plus $0.00005 per run start. Platform usage is included. Calls rejected for missing or wrong parameters are free.

Limits

• French law only (metropolitan France and overseas regions for the car registration cost). Collective agreements that improve the statutory amounts are not applied: results are the legal minimums.
• Rules are updated when the law changes (new year scales, finance laws). The date checked is in each result.
• Indicative results, not legal, tax or financial advice. For a binding answer, the official simulators and professionals remain the reference.

En français

Les calculs français que les modèles de langue ratent souvent (salaire brut et net, impôt sur le revenu, frais de notaire, indemnités de licenciement et de rupture conventionnelle, prime de précarité, barème kilométrique, TVA, carte grise, malus, import de voiture, points du permis), appelables par un agent IA. Chaque résultat donne ses sources officielles et renvoie vers la page explicative de calculons.fr. Seuls les calculs réussis sont facturés.