Side Hustle Calculator

Side income is taxed differently from employment income, and the difference is the thing most people discover too late.

Self-employment income generally has no tax withheld at source. That means the money arriving in your account is pre-tax, and a portion of it is already owed. In the US, self-employed earners also pay both halves of FICA as self-employment tax, where an employee pays one half and the employer covers the other. Setting aside a meaningful share of every payment as it arrives — rather than reconciling at year end — is what prevents an unpleasant surprise. Depending on the amount, quarterly estimated payments may be required rather than optional.

Gross revenue is also not profit. Legitimate business expenses reduce taxable income: materials, software, platform and payment processing fees, mileage, and a home office where it qualifies. Tracking them contemporaneously is far easier than reconstructing them later, and the difference between gross and net is frequently large enough to change whether the work was worth doing.

Calculate the effective hourly rate honestly. Include unpaid time — sourcing customers, admin, travel, and the platform time that generates no income — not just the hours that were directly billed. Side work often looks better per hour than it is once that overhead is counted, and knowing the real figure is what lets you decide whether to raise prices, drop the lowest-value work, or stop.

Also check for constraints before scaling: employment contracts sometimes restrict outside work or claim ownership of what you create, and some activities require registration or licensing once they pass a threshold. Everything runs in your browser — no login, no upload, and no figure you enter leaves the page.