Building a Task or Kanban Board | Column Design and WIP Limits

You built a kanban board, and now cards are piling up on the left while the same ones have sat in the middle column for weeks. The cause is not the tool but the column design and how many things you run at once. This article covers the design needed to keep a board moving.

Columns Represent the State of the Work

The first thing to settle is what a column represents.

A common mistake is making columns out of people or departments. Create columns named after individuals or teams and the cards stop moving, because the owner does not change as the work progresses.

A column shows what state the work is in: not started, in progress, awaiting review, done. Keep the owner as an attribute of the card.

Use at Most Five Columns

Finer divisions feel closer to reality, but the opposite holds.

More columns mean moving each card more often. A design where one piece of work passes through three columns eventually stops being updated at all.

Five is the guide. Past that, check whether you are dividing by state or by process step. If the columns are process steps, that belongs in a schedule chart rather than a kanban board.

Should waiting be a column?

Whether to make "awaiting review" a column or an attribute of the card is a common question.

The test is whether things get stuck there. If reviews sitting for days is a problem, make it a column and make it visible. If they clear quickly, it does not need one.

Setting the WIP Limit

A WIP limit is the maximum number of cards allowed in a column. It is the idea at the centre of kanban.

Without a ceiling, people keep starting new work. In-progress cards accumulate, and nothing finishes.

The starting number

For the in-progress column, start at roughly 1.5 times the headcount. Six cards for a team of four.

Not matching the headcount exactly is deliberate, because waiting happens. When someone is blocked on a review or a client's reply, they need room to move to something else.

How to tune it

Judge by how often you hit the limit.

If you hit it daily and work stalls, either the limit is too tight or there is a problem upstream. If you never hit it, the limit is not doing anything.

Hitting it once or twice a week is about the right level.

Define Done for Each Column

When people apply different standards for moving a card right, the board loses credibility.

Write one line under each column stating what qualifies a card to move on.

• In progress → awaiting review: the first draft is complete and self-checked