Schedule C Calculator 

Schedule C is where sole proprietors turn a year of invoices and receipts into one number the IRS cares about: net profit or loss. This calculator walks the real Schedule C path, from gross income through returns, cost of goods sold, expenses and the home office deduction, then applies the 15.3% self-employment tax to 92.35% of the profit, with the IRS $400 minimum-earnings floor built in.

Quick Answer

How to use the Schedule C calculator

Start with the only required field: your gross income for the year, which is everything clients paid you before costs. Then fill in the four deduction fields, leaving any that do not apply at zero. Click Calculate to see gross revenue, total expenses, net profit or loss, the 92.35% SE earnings base, the SE tax and what remains after it. Results stay hidden until you click Calculate, and Reset restores the worked example.

Service businesses such as writers, designers, developers and consultants usually have no cost of goods sold, so that field sits at zero for them. Product sellers, resellers and makers are the ones who need it, along with the returns field for refunds they issued.

The math, line by Schedule C line

Every input maps to a real line on Schedule C (Form 1040). The calculator follows the form's own order, which is why competitors that start from a single net-profit number cannot teach you where that number comes from.

The SE tax step then follows Schedule SE: multiply net profit by 0.9235 to get net earnings from self-employment, and apply 15.3% to that. The IRS sets the $400 floor on net earnings, so profits so small that 92.35% of them stays under $400 produce zero SE tax in this tool, matching the actual filing rule.

Worked example: a $60,000 freelance year

The calculator is pre-filled with this example, so you can reproduce every number below by clicking Calculate.

Step 1: gross revenue. $60,000 of gross income minus $1,200 in customer refunds gives $58,800 of gross revenue, which is Schedule C line 7.

Step 2: total expenses. $15,000 cost of goods sold plus $9,500 of business expenses plus a $1,800 home office deduction gives $26,300 of total expenses.

Step 3: net profit. $58,800 minus $26,300 gives $32,500. This is Schedule C line 31, the number that flows onto the rest of the return.

Step 4: self-employment tax. $32,500 times 0.9235 gives $30,013.75 of net earnings, well above the $400 floor. At 15.3%, the SE tax is $4,592.10.

Step 5: what is left. $32,500 minus $4,592.10 gives $27,907.90 after SE tax. Half of the SE tax, $2,296.05, is then deductible above the line on Schedule 1, which reduces federal income tax but not the SE tax itself.

Why only 92.35% of profit is taxed

The 92.35% factor is the IRS leveling the field between employees and the self-employed. A W-2 employee never pays Social Security and Medicare tax on the employer's half of the payroll tax, so the IRS trims 7.65% off self-employment profit before applying the 15.3% rate. That is why the effective SE tax rate on Schedule C profit is about 14.13%, not 15.3%, and the calculator shows the 92.35% earnings row so you can see the adjustment instead of taking it on faith.

This is also the single most common error in rival tools: many multiply the full net profit by 15.3% and overstate the bill by roughly 8%. The IRS states the 92.35% rule plainly in its self-employment tax guidance, and every serious competitor agrees with it.

What competing calculators miss

• NumericCore documents the 92.35% rule and the IRS source well, with a clean $80,000 worked example, but it starts from net profit. It cannot show you how gross income becomes that profit.
• taxpayers.net is strong on 2026 figures (the $184,500 wage base, the additional Medicare thresholds, the 50% deduction) but it is SE-tax-only: no Schedule C build-up at all.
• selfemployedcalc.com runs the full pipeline down to quarterly payments with the QBI deduction, yet its Schedule C step is one gross number minus one expense number. The line-by-line path is missing.
• gignomic.com walks the six form steps from Schedule C to 1040-ES, which is genuinely useful, but its calculator does not take per-line Schedule C inputs either.
• sdocpa.com states the $400 minimum threshold clearly, which most tools omit, but again computes SE tax only.
• selfemploymenttaxestimator.com handles the shared Social Security wage base for people with both W-2 and 1099 income, a real strength, but does not construct Schedule C.
• The gap this page fills: the actual Schedule C order (gross income, returns, COGS, expenses, home office), the 92.35% earnings row shown as its own line, and the $400 floor applied inside the tool, so a $300 profit correctly shows $0 of SE tax instead of a phantom $42.39 bill.

What this estimate leaves out

Honesty about the edges is what separates a planning tool from a tax return. This calculator applies the flat 15.3% to the 92.35% base and does not cap the Social Security portion at the annual wage base ($184,500 for 2026), so very high earners will see a slightly overstated SE tax. It does not add the 0.9% additional Medicare tax above $200,000 ($250,000 joint), and it computes no federal or state income tax at all. Your Schedule C net profit flows onto Form 1040, where income tax, the 50% SE tax deduction and the qualified business income deduction are figured.

Two practical notes. First, self-employed people generally pay both income tax and SE tax in quarterly estimated installments with Form 1040-ES, not in one April lump. Second, mortgage lenders usually average your last two years of Schedule C net profit when you apply as a self-employed borrower, which is why keeping this number clean matters beyond taxes; see the self-employed mortgage calculator for how lenders use it. Independent contractors estimating what to charge can use the same profit logic in reverse.

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