Scrum Estimation Techniques: Choose the Right Approach
Scrum teams use various estimation techniques to size Product Backlog items. Each technique has strengths suited to different situations. The key is selecting an approach that works for your team's context and maturity level.
Quick Answer: Estimation Techniques Comparison
| Technique | Best For | Speed | Accuracy |
|---|---|---|---|
| Planning Poker | New teams, complex items | Slow | High |
| T-Shirt Sizing | Quick rough estimates | Fast | Medium |
| Affinity Estimation | Large backlogs | Very Fast | Medium |
| Fibonacci Sequence | Sizing scale | N/A | High |
Planning Poker
The most popular estimation technique in Scrum. Team members simultaneously reveal cards with their estimates, then discuss differences to reach consensus.
How It Works:
- Product Owner presents a Product Backlog item
- Team discusses and asks clarifying questions
- Each team member selects a card privately
- All cards revealed simultaneously
- High and low estimators explain their reasoning
- Team re-estimates until consensus is reached
Best for: Teams learning to estimate, complex or uncertain items, building shared understanding.
T-Shirt Sizing
A quick, intuitive approach using t-shirt sizes (XS, S, M, L, XL, XXL) instead of numbers.
Benefits:
- Non-technical stakeholders understand easily
- Removes the illusion of precision
- Very fast for initial sizing
Best for: Initial backlog sizing, roadmap planning, quick categorization.
Affinity Estimation
Also called "bucket estimation" — rapidly sort items into groups based on relative size.
How It Works:
- Place reference items at different size levels
- Team silently places items next to similar-sized work
- Discuss and adjust any disagreements
- Convert groups to story points if needed
Best for: Sizing a large backlog quickly, newly formed teams, initial release planning.
The Fibonacci Sequence
Not a technique itself, but the most common scale used for story points: 1, 2, 3, 5, 8, 13, 21...
Why Fibonacci?
- Gaps increase with size, reflecting greater uncertainty
- Prevents false precision for large items
- Forces choice between distinct values
Explore each technique in detail below to find the best fit for your team.
Scrum Planning and Estimation - Estimation Techniques
Scrum Planning and
Estimation - Estimation Techniques