A project quote is the fixed price you give a client for a defined piece of work, instead of billing them hour by hour. Getting it right means starting from your real costs — your time and any out-of-pocket expenses — and then adding a margin large enough to cover the risk of fixed-price work. This page walks through exactly how the calculator above turns your inputs into a quote, with a full worked example you can check by hand.
How the project quote is calculated
The calculator works in three steps, moving from your time and expenses to a final number:
Labor cost = Estimated hours × Hourly rate
Base cost = Labor cost + Project expenses
Quote = Base cost ÷ (1 − Profit margin ÷ 100)
First, labor cost is just your estimated hours multiplied by your normal hourly rate — what your time on this project is worth. Add your project expenses (materials, subcontractors, software bought specifically for this job) and you get base cost: the true cost of delivering the project before any profit.
The last step is where people often get tripped up. Instead of multiplying base cost by something like 1.20 to add a 20% margin, the calculator divides base cost by (1 − margin). This makes the margin a percentage of the quote, not a percentage of the cost. The calculator also reports profit included, which is simply the quote minus the base cost — the actual dollar amount of margin you’re building in.
A worked example
Say you estimate a project will take 40 hours, billed at your normal rate of $75 per hour. You expect $200 in expenses — say, a stock photo license and a small subcontracted task. You want a 20% margin built into the price to cover the risk of fixed-price work.
First, labor cost: 40 hours × $75 = $3,000.
Next, add expenses to get base cost: $3,000 + $200 = $3,200.
Now apply the margin. Instead of adding 20% to the cost directly, divide by (1 − 0.20), which is 0.8: $3,200 ÷ 0.8 = $4,000.
That $4,000 is your quote. The profit included is the quote minus the base cost: $4,000 − $3,200 = $800, which is exactly 20% of the $4,000 quote — confirming the margin landed where you intended.
Why dividing by the margin isn’t the same as a markup
It’s easy to assume a “20% margin” and a “20% markup” produce the same number, but they don’t. A markup of 20% multiplies cost by 1.20: $3,200 × 1.20 = $3,840, giving you $640 of profit — which is only 16.7% of that $3,840 price, not 20%. Dividing by (1 − margin) instead, as this calculator does, guarantees the margin percentage you enter is the actual share of profit in the final price the client pays. If you’re used to thinking in markups, see the markup calculator for that version of the math side by side.
What else affects your quote
This calculator gives you a starting number based on the inputs you provide — it’s an estimate, not a guarantee the project will land exactly there. A few things shift the real outcome:
- How accurate your hour estimate is. The single biggest risk in fixed-price work is underestimating hours. If the job runs long, your real hourly return drops below the rate you planned for, regardless of what the quote said.
- Scope changes. Anything added to the project after you’ve quoted it isn’t covered by this number unless you re-run the calculation with updated hours or expenses.
- How well you know the client and the work. Vague briefs, new clients, or unfamiliar types of work all carry more uncertainty — a reason to lean toward a larger margin rather than a smaller one.
- What competitors are charging. The calculator tells you what you need to charge to hit your margin; it doesn’t check that number against the market. Compare it with what similar projects typically go for before sending it.
Plug your own hours, rate, expenses and margin into the calculator above to get a number specific to your project. Treat the result as your starting point for a quote, then adjust the margin until it reflects how much risk and uncertainty this particular job carries.