Tools · 2026 · 1099

Self-employment tax calculator

Schedule C net profit → SE tax, federal income tax, a quarterly 1040-ES number, and SEP vs solo 401(k) room. Read the self-employment tax guide first. This is not Schedule SE, not an S-corp model, and not a filing.

Quick answer: This calculator estimates self-employment tax on net profit, quarterly estimates, and SEP versus solo 401(k) room using the 2026 wage base and rates already printed on the page. It is not a Form 1040-ES filing.

Schedule C net profit (after expenses) Filing status Age this year W-2 Social Security / Medicare wages (optional) Federal withholding already on the W-2

State income tax % (rough) Prior-year total federal tax (safe harbor) Prior-year AGI QBI 20% deduction Model retirement contribution as

Federal tax this year

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Educational estimate using Rev. Proc. 2025-32 brackets, SSA 2026 wage base $184,500, Notice 2025-67 415(c) $72,000, and Publication 560’s 20% self-employed rate. No NIIT, no extra standard deduction for age/blind, no SSTB wage/UBIA phase-out math. Need a rate first? Freelance rate calculator (optional tip). Sequence: PayPal playbook.

What this means for you

What this means for you: self-employment tax is not your whole income tax. The page applies the percent it prints to 92.35% of net profit and stops Social Security at the wage base. Retirement room is limited by net profit and the caps on the page. A freelance hourly rate is a different calculator.

How to use this calculator

Open the Self-employment tax calculator and keep the sample numbers or replace them with your own. The result updates as you type.
Read the headline figure first, then the breakdown or chart under it.
Use Copy share link if you want those inputs in the URL. The page is an educational estimate, not a filing, approval, or recommendation.

FAQ

What profit does self-employment tax use?

The page uses net profit times 92.35%, then the Social Security and Medicare rates it prints, with Social Security stopping at the wage base.

Is the quarterly number a voucher?

It is an estimate of the year's tax spread across four payments. Penalties, credits, and withholding from a W-2 job can change the real voucher.

SEP or solo 401(k)?

The page compares contribution room from the profit and caps it already encodes. It does not open an account.

Educational, not financial advice. Page updated October 24, 2026 — no tax, limit, or rate figure was changed in this review.

Optional

Tip / Support

This self-employment tax calculator is free. A voluntary tip supports this classroom — not a paywall, not tax software, not ads.

WhatIfInLearning

Optional classroom tip

$4.99 USD

Processed by PayPal as a WhatIfInLearning tip. Optional — never required to use the calculator.