What is a bar chart?
A bar chart represents quantities by the height of rectangles, one per category. It's the most commonly used chart in business — multiple items lined up side by side make differences easy to spot at a glance. Because the relative size of values reads instantly, bar charts work especially well in slide decks and reports.
If you're not sure which chart to reach for, start with a bar chart. About nine times out of ten, it does the job.
When to use it
Tips for making one well
1. Don't overload with categories
Bar charts read best with around five to seven categories. If you have more than ten, narrow down to the important ones, or consider a horizontal bar chart instead.
2. Sort by value
When category order doesn't carry meaning (departments, products, etc.), sort by value — usually largest to smallest. The eye flows naturally and comparisons get easier. For time-series (month, year), keep the natural order intact.
3. Limit colors to one or two
For a single-series comparison, a single color is the cleanest choice. Using one accent color to highlight a key item is also effective.
4. Always start the axis at zero
Bar charts use length to encode quantity, so the Y-axis must start at zero. Starting partway up creates a misleading "exaggeration chart" where small differences look large.