Fixed fee or day rate: which actually earns more?

A fixed project fee hands the client certainty. It also hands you all the delivery risk. This calculator does the two trade-offs that matter: at your planned effort, which option earns more? And once you factor in a realistic overrun risk, does the project fee still win?

Project fee vs day rate

When each wins

Project fee wins when:

• Scope is tight, well-defined and small enough to control (think 5-15 days).
• You can deliver more efficiently than the market because of templates, tooling or domain knowledge.
• The client values certainty enough to pay a premium.

Day rate wins when:

• Scope is unclear or likely to change.
• The project involves materially new work for you (no efficiency arbitrage).
• Dependencies are outside your control (client delays, third-party integration, etc.).

A fallback worth considering: a day rate with a "not to exceed" cap. You stop the clock at the cap and anything above is a change request. It gives the client certainty and you a fair rate for the base effort.