Build a complete project cost estimate from first principles. Enter team roles, hours per phase, overhead rate and contingency buffer to see full project cost — and the minimum viable budget to start.
Team composition and hours:
Project cost estimation is consistently optimistic due to the planning fallacy: humans systematically underestimate task duration and cost while overestimating their ability to deliver. Research by Roger Buehler found that even when people knew their past projects had run over, they still predicted their current project would finish on time. A mandatory contingency buffer is not pessimism — it is statistical realism.
Studies consistently show knowledge work projects run 40–200% over initial estimate on average. A 15% contingency buffer does not fully account for this — it is a minimum floor. For complex, novel or cross-functional projects, 25–40% contingency is more appropriate. The alternative to explicit contingency is implicit overrun — which is more damaging because it is unmanaged and surprises stakeholders. Build contingency in; manage it explicitly.
Use three-point estimation for each task: optimistic (O), most likely (M), pessimistic (P). PERT estimate = (O + 4M + P) / 6. This reduces the planning fallacy by forcing consideration of worst cases. Add 15-25% contingency on top. For complex projects: analogous estimation (compare to similar past projects with actuals) outperforms bottom-up estimation. Track actual vs estimated time on all projects to calibrate future estimates.