Calculators
Change Order Calculator
Price a construction change order from labour, materials, markup and schedule impact, and update the contract total.
- Runs in your browser
- Nothing uploaded
The tool
Enter your numbers below. Results update as you type, and nothing leaves your browser.
Everything you enter stays on your own machine. Nothing is sent to us or to anyone else, which you can confirm in your browser network tab.
What people use it for
- Pricing client-requested changes
- Tracking contract value
- Documenting scope changes
- Training project managers
About this tool
What the Change Order Calculator does
A change order prices work added to or removed from a contract. It should include labour, materials and equipment for the change, markup for overhead and profit, and the cost of any extra time on site, such as supervision and site costs for added days.
Formula
- Direct cost = Σ hours × rate + materials
- Change order = direct cost × (1 + markup) + extra days × daily site costs
- Revised contract = original + approved changes + this change
Worked example
Using the starting values in the calculator above:
| Input | Value |
|---|---|
| Original contract value | $150,000 |
| Approved changes to date | $6,500 |
| Change items | 2 entries |
| Overhead and profit markup | 15% |
| Extra days on site | 3 |
| Daily site costs | $400 |
| Result | Value |
|---|---|
| Change order price | $5,030 |
| Revised contract value | $161,530 |
| Direct cost of the change | $3,330 |
| Total change from original contract | 7.7% |
How to read the result
Get every change order signed before doing the work; verbal approvals are the start of most payment disputes.
Include time impact as well as cost, so the completion date moves with the scope.
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Questions
Questions about this tool
The things clients actually want to know — costs, timelines, ownership and what happens after launch.
A description of the change, its price, the effect on the schedule and signatures from both parties.
Usually yes, for overhead and profit, as allowed by the contract.
Pause the extra work and follow the contract's dispute process.
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