Calculator
Side Hustle ROI Calculator
Work out the real hourly rate of a freelance project after tax, expenses, and the unpaid hours nobody quotes for. See whether the gig is actually worth saying yes to.
The project
Time actually spent on the work itself.
Quoting, scoping, calls, contracts, revisions, chasing payment.
Software, stock images, subcontractors, travel, materials.
Tax & overhead
UK self-employed: roughly 29% (20% income tax + 6% Class 4 NI on profits in the basic-rate band, plus a buffer). Higher-rate earners use ~42%.
Optional: share of your fixed monthly costs (accountant, software subs, insurance) you want to attribute to this project.
What you want to earn per hour, take-home. Used for the verdict.
Calculations happen entirely in your browser. Nothing is saved or sent.
Where the money goes
To match your target
"Effective hourly rate" divides take-home by every hour you spend on the project — billable and unpaid. This is the number that actually matters when you're choosing between gigs.
How the side hustle ROI calculator works
The headline rate on a freelance project is almost never the rate you actually earn. Tax eats a chunk, expenses eat another, and the hours you spend on emails, revisions, invoicing and chasing payment are all unpaid. This calculator strips it back to what really matters: your effective hourly rate after everything.
What's deducted
- Tax — your marginal income tax rate on side earnings (plus self-employment NI if applicable).
- Expenses — software, materials, mileage, anything you'd not buy without the gig.
- Unpaid hours — admin, emails, revisions, scoping calls. Add them on top of the billable hours.
Effective rate = (Fee − Expenses − Tax) ÷ (Billable hours + Unpaid hours)
Worked example
Scenario: £800 project. Quoted 8 hours; realistically 12 once you include scoping calls, revisions, invoicing. £80 of software/expenses. UK basic-rate side income (20% tax + 6% NI = 26%).
Profit before tax: £800 − £80 = £720
Tax: £720 × 26% = £187
Net: £533
True hours: 12
Effective hourly rate: £533 ÷ 12 = £44/hr — vs the £100/hr the £800/8h headline implies.
Frequently asked questions
What is the 'true' hourly rate of a side hustle?
It's what's left after subtracting tax, expenses, and the unpaid time you spend on a project. A £500 fixed-price job that quotes 5 hours of work but takes 8 hours including emails, revisions and admin — at a 30% effective tax rate, with £50 of expenses — actually pays you £39/hour, not £100/hour.
What tax rate should I use?
For UK side income on top of a salaried job, most people are at the 20% Basic-rate boundary — but you'll also pay Class 4 NI at 6%, so 26% is a good baseline. Higher-rate taxpayers should use 40% + 2% = 42%. US contractors should add federal bracket + state tax + 15.3% self-employment tax.
Should I include time for invoicing and admin?
Yes — every hour you spend chasing payment, doing your books, or dealing with client emails is unpaid time that drags your effective rate down. A 5-hour project plus 1.5 hours of admin is really 6.5 hours. Track real time for a couple of months and you'll be surprised.
What's a profitable side hustle hourly rate?
Compare it to your day-job hourly rate (gross salary ÷ 1,920 working hours). If the side hustle pays less per hour after all costs, you're effectively earning less than your full-time job for the inconvenience. Many side gigs only break even on this comparison.
Are expenses tax-deductible?
In the UK and US, legitimate business expenses (software, equipment used for the work, mileage, a portion of home office) reduce your taxable profit. Keep receipts and consider registering for self-assessment in the UK or filing a Schedule C in the US once your side income is meaningful.
Is the gig worth taking?
That's the question this calculator is built around. If your effective hourly rate beats your day job and you'd rather do the work than the alternative use of those hours (rest, family, learning), it's a yes. If not, decline politely or quote higher.