Agile estimation glossary
The words you hear in refinement and sprint planning, explained in a sentence or two.
- Acceptance criteria
- The conditions a backlog item must meet to be accepted as done. Clear criteria are the biggest single help to a good estimate, because they say what “finished” means. Read the guide
- Affinity estimation
- A fast technique for sizing many items at once: the team silently arranges items on a wall from smallest to largest, then groups them into sizes. Useful for a large backlog before planning poker refines the detail. Read the guide
- Anchoring
- The tendency to stick close to the first number you hear. Planning poker reduces it by having everyone choose a card in secret and reveal together. Read the guide
- Async estimation
- Estimating on your own time instead of in a live meeting: everyone votes before a due date, then the team reviews the spread together. Helpful for distributed teams across time zones. Read the guide
- Backlog
- The ordered list of everything the team might work on. The product owner keeps it in order; the team refines and estimates the items near the top. Read the guide
- Backlog refinement
- The ongoing activity of adding detail, splitting and estimating backlog items so they are ready for a sprint. Also called backlog grooming. Planning poker usually happens here. Read the guide
- Bucket system
- An estimation technique where items are placed into buckets labelled with point values. Faster than planning poker for large numbers of items, at the cost of less discussion. Read the guide
- Capacity
- How much work a team can take on in a sprint, given holidays, meetings and other commitments. Velocity tells you what the team has done; capacity tells you what is possible this time. Read the guide
- Coffee card
- A card in some planning poker decks that means “I need a break”. In SprintPoker it is the Break card, an optional card a moderator can switch on in Session Settings.
- Cone of uncertainty
- The idea that estimates are least accurate at the start of work and become more accurate as you learn. It is why larger, vaguer items get larger, wider numbers. Read the guide
- Consensus
- Agreement the whole team can live with. In planning poker you reach it by discussing the highest and lowest votes, then re-estimating, rather than by averaging. Read the guide
- Definition of Done
- The shared checklist every item must meet before it counts as complete, such as tested, reviewed and documented. Estimates should include the work the Definition of Done requires. Read the guide
- Definition of Ready
- A team’s agreement on what an item needs before it can enter a sprint: for example a clear goal, acceptance criteria and an estimate. Read the guide
- Epic
- A large body of work that is split into smaller stories. Epics are usually too big to estimate with planning poker until they are broken down. Read the guide
- Estimate
- A team’s judgement of the size of an item. In agile teams estimates are relative (this is about twice that) rather than promises of hours. Read the guide
- Facilitator
- The person who runs the session: keeps time, makes sure quieter people are heard and moves the team on. In SprintPoker this is the moderator. Read the guide
- Fibonacci sequence
- The number series 1, 2, 3, 5, 8, 13, 21 and so on, where each number is the sum of the two before it. The widening gaps match the growing uncertainty of bigger items. Read the guide
- Forecast
- A range of likely outcomes, based on past velocity, for when work might be done. Better than a single date because it is honest about uncertainty. Read the guide
- Moderator
- In SprintPoker, a moderator runs the round: finishes voting, chooses the final estimate with Save & Next, re-estimates and sets the timer. The host is always a moderator, and guests can’t be moderators, so in a guest session the host is the only moderator. Read the guide
- Modified Fibonacci
- A planning poker scale that keeps the Fibonacci shape for small numbers and rounds the large ones: 0, ½, 1, 2, 3, 5, 8, 13, 20, 40, 100. Read the guide
- #NoEstimates
- A movement that questions the value of estimating at all, preferring to slice work small and count items. Many teams take ideas from it while still estimating. Read the guide
- Observer
- Someone who watches a planning poker session without voting, such as a stakeholder. In SprintPoker people choose to vote or just watch when they join.
- Planning poker
- A consensus-based estimation technique: each person picks a card in secret, everyone reveals together, and the team discusses the differences before agreeing. Also called Scrum poker or pointing poker. Read the guide
- Product owner
- The person accountable for the product backlog and its order. They explain items during estimation and answer questions, but usually do not vote. Read the guide
- Re-estimate
- Voting again on the same item after a discussion. In SprintPoker a moderator starts a new round with Re-estimate. Read the guide
- Reference story
- A finished item the team agrees represents a particular size, used to compare new items against. In sessions on a Laya board or a Jira board, SprintPoker shows Reference Issues and Matching Issues for this. Read the guide
- Relative estimation
- Estimating by comparing items with each other (this is bigger than that) instead of in absolute time. People are much better at comparing than at predicting hours. Read the guide
- Remote estimation
- Running planning poker with people in different places, using an online tool so everyone can vote and reveal at the same moment. Read the guide
- Save & Next
- SprintPoker’s button that records the agreed estimate and moves to the next item. For Jira issues it can also write the estimate back to Jira.
- Scrum
- A widely used agile framework built around short sprints, a product backlog and regular inspection and adaptation. Read the guide
- Scrum poker
- Another name for planning poker, common among Scrum teams. Read the guide
- Spike
- A short, time-boxed piece of research to reduce uncertainty, often used when an item is too unclear to estimate. Read the guide
- Sprint
- A fixed period, usually one to four weeks, in which a Scrum team delivers a usable increment. Read the guide
- Sprint planning
- The meeting at the start of a sprint where the team chooses the sprint goal and the items it will work on. Read the guide
- Story point
- A unit of relative size that blends effort, complexity and uncertainty. A 5 is roughly bigger than a 3 and smaller than an 8; it is not a number of hours. Read the guide
- T-shirt sizing
- Estimating with sizes such as XS, S, M, L and XL. Good for early, rough estimates and for teams new to estimation. Read the guide
- Timebox
- A fixed amount of time for an activity. A short timer on each planning poker round keeps discussion focused. Read the guide
- User story
- A short description of a feature from the user’s point of view, often written as “As a … I want … so that …”. Read the guide
- Velocity
- The amount of work, usually in story points, a team completes in a sprint. Useful for forecasting the team’s own future, and meaningless for comparing teams. Read the guide
- Wideband Delphi
- The estimation method planning poker grew from: experts estimate anonymously, discuss and repeat until estimates converge. Read the guide