Your break-even is not a price — it is a clock
In fixed-price work, break-even moves every day the project runs. Same fee, nine extra days, and a healthy margin is a loss. Here is the math.
The fee is fixed. The clock is not
Most people think of break-even as a price: the number where revenue covers cost and anything above it is profit. In fixed-price work that picture is incomplete, because your cost is a function of time and the fee is not.
Every working day the project runs, it burns money: salaries, the overhead behind them, the tools, the review time. The client pays you once, for a scope, not for the days. So the real question is not "what price covers my cost" but "how many days does my fee buy before the project is underwater."
The chain is simple: daily burn multiplied by the number of days on the project is your cost. Your quote only covers the days you happened to model. Schedule risk is cost risk, dollar for dollar.
A worked example: the nine days that ate the margin
Take a fixed-price job at $60,000. Your fully loaded burn is $1,400 a day. Your three-point estimates on the tasks, summed the usual way, land on a median duration of 38 days.
Cost at 38 days: $53,200. Margin: $6,800, about 11%. Looks like a deal worth signing.
But your estimates are ranges, and durations vary. The P80 duration for the same project is 47 days. Nine extra days, and the arithmetic changes completely:
| Duration | Cost | Margin | Result |
|---|---|---|---|
| P50 — 38 days | $53,200 | +$6,800 | +11% |
| Break-even — 42.9 days | $60,000 | $0 | 0% |
| P80 — 47 days | $65,800 | -$5,800 | -9.7% |
| P90 — 53 days | $74,200 | -$14,200 | -23.7% |
The quote did not fail on price. It failed on duration. At the median the deal is fine; at the 80th percentile it is a loss, and losses at the 80th percentile happen roughly one job in five.
Now flip the question around. To hold the same 11% margin at the 47-day duration, the fee would need to be about $73,700 — 23% above the $60,000 you quoted. That gap is the real price of schedule risk, and a price-only view of break-even cannot see it.
Why the simple break-even calculator lies to you
A price built from median hours times a rate assumes every project lands exactly on its median. That is not how projects behave. Fixed-price profitability lives at the tail, not the middle.
The useful question is the reverse one: given your burn and your duration distribution, what fee keeps margin above zero at the P80 duration? The break-even calculator works that out from your burn, and the fixed-price project calculator shows the full cost picture task by task. Use both before you quote, not after you lose.
When the clock runs against you
Three habits keep the clock from eating the job. First, quote from a duration percentile, not from the median — put your margin on the calendar, not just on the rate card. Second, track burn against the plan weekly, so a drifting project shows up at week two rather than week eight. Third, negotiate around named risks instead of blanket padding: a client who accepts a review deadline and a decision date has done more for your margin than any 10% uplift.
The clock runs whether a risk fires or not. A risk that never materializes still costs you the days you waited on it.
The takeaway
Your break-even is not a number on a spreadsheet; it is the day your fee stops covering the burn. A 60k job with a 1,400-a-day burn and a realistic P80 of 47 days is a loss waiting to happen, and the median of 38 days will not warn you. Model the duration distribution, price the tail, and watch the clock. The app simulates the whole schedule against your burn and shows the margin at every percentile, and the one-time license keeps the arithmetic on your side for every job after this one.