What happens if the project runs over
With a fixed price, you're paid the same however long the work takes. If it runs over, your real hourly rate falls. This table uses your numbers above. The effective rate is what you earn per hour after project costs.
| Project takes | Actual hours | Effective hourly rate |
|---|---|---|
| Enter your numbers above to see this table. | ||
How to use this calculator
- Estimate the hours. Break the project into tasks and add them up. Include calls, emails and revisions.
- Enter your hourly rate. If you don't have one yet, work it out with our hourly rate calculator.
- Add project costs you'll pay for, such as fonts, stock photos, software or subcontractors.
- Choose a buffer and deposit. 10–20% buffer and a 25–50% deposit are common.
How it's calculated
Worked example
Sam is a web developer quoting for a small website. They estimate 40 hours at $75 an hour, with $200 of costs for a premium theme and plugins. They add a 15% buffer and ask for 50% upfront.
Sam should quote $3,680 and invoice $1,840 before starting. If the project takes 50 hours instead of 40, Sam still earns $69.60 an hour, which is less than the target rate but well above zero. That's what the buffer is for.
Tip: write down what the price includes, such as the number of revision rounds. Anything outside that list becomes a new quote, so extra work doesn't eat into your buffer.
Frequently asked questions
How big should my safety buffer be?
10–20% suits most projects you've done before. For new kinds of work, unclear briefs or clients who change their minds often, 25–30% is safer.
Why ask for a deposit?
A deposit shows the client is committed, covers your costs early and reduces the risk of doing work that never gets paid. Many freelancers ask for 25–50% before starting.
Should I show clients my hourly rate?
You don't have to. Many freelancers quote only the project price. Clients then focus on the result rather than the hours, and you keep the benefit if you work efficiently.
What if a client pays late?
Put your payment terms and any late-payment interest in your contract or invoice. In the UK, businesses can usually claim statutory interest on late invoices from other businesses. Our late payment interest calculator works it out.