How does estimation work in agile?

Agile estimation sizes work by relative effort rather than exact hours. Instead of “this will take 6 hours,” teams ask “how big is this compared to that?” — usually in story points. It sounds looser than an hourly estimate, but over time it’s often more reliable, because people are better at comparing sizes than predicting durations.

Story points and why they’re used

Story points are a unit of relative size that bundle effort, complexity, and uncertainty into one number. A 5-point story is roughly five times a 1-pointer. Because points are relative, they sidestep the false precision of hour estimates and travel better across a team, where one person’s “2 hours” is another’s “half a day.”

Planning poker

Planning poker is the common technique for estimating together: the team reveals point estimates simultaneously, discusses the outliers, and converges. The discussion is the real value — a big spread usually means the story isn’t well understood yet, which is worth catching before the work starts.

Velocity turns estimates into plans

Once a team estimates in points, velocity — the points completed per sprint — becomes a planning tool. Knowing your team reliably delivers, say, 30 points a sprint lets you forecast how much of the backlog fits in the next few sprints, without pretending you can predict each task to the hour.