Self-Employment Tax Calculator (US)
How much Social Security and Medicare tax do I owe on my self-employment income?
Single calculationv1.0.0Verified 2026-11-01Runs in your browser
Spec sheet
schedule_se_long_form · v1.0.0Method
Schedule SE with Form 8959 Additional Medicare Tax
- 01
NE = net profit × 92.35 % (no SE tax if NE < $400) - 02
Social Security = 12.4 % × min(NE, wage base − W-2 wages) - 03
Medicare = 2.9 % × NE - 04
Additional Medicare = 0.9 % × max(0, NE − (threshold − W-2 wages)) - 05
Deductible = ½ × (Social Security + Medicare)
Limits — read before relying on it
- Income tax is not included — only Social Security and Medicare (SE tax) and Additional Medicare Tax.
- Church employee income, farm optional method and non-farm optional method are not modeled.
- Additional Medicare uses W-2 Medicare wages equal to the W-2 wages entered.
Sources
- IRS — Self-employment tax ↗official data
- SSA — Contribution and benefit base ↗official data
Reference data
OCG knowledge packsRates and rules this calculator reads, stored as versioned OCG facts with a source and validity period. Facts marked “pending review” are used with a warning until a person verifies them against the source.
U.S. Social Security & Medicare (FICA / SECA) parameterslogic:pack:us_irs:fica_self_employment · v2026.1.0
| Parameter | Value | Valid | Status |
|---|---|---|---|
| Social Security contribution and benefit base | 147000 USD | 2022-01-01 → 2023-01-01 | accepted |
| Social Security contribution and benefit base | 160200 USD | 2023-01-01 → 2024-01-01 | accepted |
| Social Security contribution and benefit base | 168600 USD | 2024-01-01 → 2025-01-01 | accepted |
| Social Security contribution and benefit base | 176100 USD | 2025-01-01 → 2026-01-01 | accepted |
| Social Security contribution and benefit base | 184500 USD | 2026-01-01 → 2027-01-01 | pending review |
| Self-employment Social Security (OASDI) rate | 0.124 | 1990-01-01 → | accepted |
| Self-employment Medicare (HI) rate | 0.029 | 1990-01-01 → | accepted |
| Additional Medicare Tax rate | 0.009 | 2013-01-01 → | accepted |
| Additional Medicare threshold — single / HoH / QSS | 200000 USD | 2013-01-01 → | accepted |
| Additional Medicare threshold — married filing jointly | 250000 USD | 2013-01-01 → | accepted |
| Additional Medicare threshold — married filing separately | 125000 USD | 2013-01-01 → | accepted |
| Net earnings factor (100 % − 7.65 %) | 0.9235 | 1990-01-01 → | accepted |
| Minimum net earnings subject to SE tax | 400 USD | 1990-01-01 → | accepted |