Histogram Maker
Make a histogram from a list of numbers with automatic or custom bins, a frequency table and summary statistics. Your work stays on this device whenever possible.
How to use Histogram Maker
- Paste your numbers, separated by spaces, commas or new lines (a column copied from a spreadsheet works).
- Keep the automatic bins, or pick a rule, a number of bins, or a bin width and a start value.
- Tick "relative frequency" to show percentages instead of counts.
- Download the histogram as SVG or PNG, or the bin counts as CSV; the frequency table is under the chart.
Worked example
Delivery times for 200 orders, with automatic Sturges bins, show most orders taking 2 to 4 days and a long tail out to 11 days. Switching to Freedman–Diaconis gives narrower bins that show a second small peak at 7 days: orders from a remote warehouse.
When to use this tool
- Statistics assignments that need a histogram and a frequency table.
- Seeing the spread of response times, prices or test scores at a glance.
Important limitations
Makes one histogram of one data set at a time; overlaid or grouped histograms are not available.
Frequently asked questions
How many bins should a histogram have?
Sturges' rule (1 + log₂ n bins) suits most data sets up to a few hundred values. The square-root rule gives more bins for larger sets, and Freedman–Diaconis adapts the bin width to the spread of the middle 50% of the data, which works well when there are outliers.
Which bin does a value on a boundary go into?
Each bin includes its lower edge and excludes its upper edge, so 70 goes into 70–80, not 60–70. The last bin also includes the maximum value.
What is the difference between a histogram and a bar graph?
A histogram shows how numeric values are spread over continuous ranges, so the bars touch. A bar graph compares separate categories. For categories, use the Bar Graph Maker.
Which standard deviation is shown?
The sample standard deviation, which divides by n − 1. This is what Excel's STDEV.S and most statistics courses use.
Is my data uploaded?
No. Everything is calculated and drawn in your browser.