How this works
France's impôt sur le revenu is a progressive bracket tax (0 / 11 / 30 / 41 / 45 %) computed on revenu net imposable. The calculator first applies the 10 % abattement professionnel (capped at €14,171, floored at €504) for salaried income, then applies the quotient familial: gross taxable income is divided by the number of parts (single = 1, couple = 2), the bracket walk runs on the per-part figure, and the result is multiplied back by the number of parts. This is the lever that makes a single earner of €70,000 in a couple pay less than a single earner of €70,000 living alone. Children add half a part each (capped at 1.5 for the third onward) but aren't modelled here — for an estimator they introduce complexity without changing the order of magnitude. CSG / CRDS (~9.7 % of most income) is a separate prélèvement social levied at source and isn't part of impôt sur le revenu, so it's not included.
The formula
Tranches 2024 (revenus 2023): 0 % up to €11,294 · 11 % up to €28,797 · 30 % up to €82,341 · 41 % up to €177,106 · 45 % beyond. The abattement pro applies to salaried income only; frais réels is the alternative if you have receipts above the cap. The plafonnement du quotient familial limits the per-half-part benefit to €1,759 (2024) — not modelled here because it kicks in at top brackets the estimator already approximates. Excludes the décote (low-income rebate), réductions et crédits d'impôt, and the prélèvement à la source mechanism (which just changes timing, not the annual total).
Example calculation
- Single, salary €35,000.
- Abattement pro = max(504, min(35,000 × 10 %, 14,171)) = €3,500 → revenu net imposable = €31,500.
- 1 part: 0 % on first €11,294 + 11 % on (28,797 − 11,294) + 30 % on (31,500 − 28,797) = 0 + €1,925 + €811 ≈ €2,736. Effective rate ~7.8 %, net ≈ €32,264.
Frequently asked questions
Why is CSG / CRDS not included?
They're prélèvements sociaux, not impôt sur le revenu. CSG (9.2 % on activity income) and CRDS (0.5 %) are deducted at source, fund Sécurité sociale, and run on a separate base from impôt sur le revenu. Most people see them on their payslip before any IR thinking. Add ~9.7 % of gross to get an all-in view of what leaves your bank account beyond impôt sur le revenu.
How does prélèvement à la source change my tax?
It doesn't change the annual total — only the timing. Since 2019, the DGFiP gives your employer a monthly rate to withhold, based on last year's filing. The May tax return reconciles, refunding any over-withholding or charging you the shortfall. The figure this calculator estimates is the annual total; your monthly take-home will already reflect roughly 1/12 of it via the prélèvement.
Why no field for children?
Children add half a part for the first two and a full part from the third — but the plafonnement caps the benefit per half-part at €1,759 (2024), so the effective saving rarely exceeds €3,500 / child / year. The interaction with single-parent status, alternating custody, and the avantage maximum quickly stops being estimator-shaped territory. For a single salary in a two-parent household the order of magnitude already matches what you'd see on the FIP; for more detail use the official simulator on impots.gouv.fr.