← All tools Budget, timeline & scope calculator

Cost, time, scope — pick two, the third moves

Build the cushion into your budget and timeline, then see what happens to both the moment scope grows. That's the whole iron triangle in one page.

Budget contingency

The book's rule of thumb: 10–20%, set aside for the risks you identified, not casual scope creep.
Total budget
$0
Baseline Contingency

Timeline buffer

Real life has meetings, sick days, and approvals that sit in someone's inbox. Skipping this is the most common rookie mistake.
Realistic duration
0 days
Estimate Buffer

Scope growth

The one PMs forget to size up. Every item added after baseline has to come out of budget, timeline, or quality — it can't come from nowhere.

Scope growth
0%
Baseline scope Added scope
What that growth costs you, if you hold quality constant