Project Cost Estimation — How to Calculate Accurately

Use the Free Calculator

Try our Percentage Calculator — instant results, no sign-up.

Overview

Cost overruns plague construction, IT, and business projects. Understanding how to build accurate estimates with appropriate contingency prevents budget disasters.

The Formula

Total budget = Direct costs + Indirect costs + Contingency (10-20%) + Profit margin

Standard formula used by professionals worldwide

Worked Example

Step-by-step

Materials 500k + Labour 300k + Overheads 100k = 900k direct | +15% contingency = 135k | Total estimate 1,035,000

Key Points

Accuracy: Results are as accurate as your inputs
Units: Always use consistent units throughout
Privacy: All CalcHub Pro calculations run in your browser — no data sent anywhere

Frequently Asked Questions

What contingency percentage is appropriate?

10% for well-defined projects. 15-20% for complex or novel work. 25%+ for high uncertainty.

What is scope creep?

Gradual addition of features or requirements beyond original scope. Primary cause of cost overruns.

How do I estimate labour costs?

Hours × hourly rate. Add 20-30% for employer costs (NI, pension, overhead allocation).

𝕏 Share 💬 WhatsApp

Ready to Calculate?

Free, instant, no sign-up.

Open Percentage →