What is Planning Poker?

Planning Poker (also known as Scrum Poker) is a consensus-based agile estimation technique used by development teams to estimate the relative effort of user stories. It was first described by James Grenning in 2002 and popularised by Mike Cohn.

How a session works

1. The team selects a user story and the product owner reads it aloud.
2. Each team member privately selects a card representing their estimate.
3. All cards are revealed simultaneously.
4. If estimates differ significantly, the high and low estimators explain their reasoning.
5. The team votes again until consensus is reached.
6. The final estimate is recorded.

Why teams use it

• Reduces anchoring bias — simultaneous reveal prevents early estimates from influencing others.
• Encourages discussion — outlier estimates surface hidden complexity or misunderstandings.
• Builds shared understanding — the estimation process itself improves team knowledge.

Card decks explained

Fibonacci (1, 2, 3, 5, 8, 13, 21…)

The most common deck. The growing gaps between numbers reflect the fact that estimation precision decreases as size increases.

T-shirt sizes (XS, S, M, L, XL, XXL)

Useful for high-level estimation where numeric precision is not meaningful. Good for roadmap planning.

Powers of 2 (1, 2, 4, 8, 16, 32, 64)

Emphasises exponential growth in complexity. Used by teams who prefer a steeper scale.

Special cards

• ?— “I don't know / I need more information”
• ☕— “I need a break” or “this story is too complex to estimate now”

Ready to try it?

Start a free session now — no registration required.