Histogram Maker (with Frequency Table)
Paste your data to draw a histogram and a frequency table.
How to make a histogram
Paste your numbers (separated by spaces, commas or new lines). The tool counts how many values fall into each bar, draws the histogram and gives you a frequency table with relative and cumulative percentages. Choose a bar width or a number of bars, or leave both at 0 and the tool picks a round bar width using Sturges’ rule.
Worked example
The default data are 40 exam scores from 55 to 98, with a mean of 80.97, a median of 82.5 and a standard deviation of 10.75. With bars 10 points wide, the counts are 2 (50 to 60), 4 (60 to 70), 10 (70 to 80), 14 (80 to 90) and 10 (90 to 100). The most common band is 80 to 90, and the long tail to the left shows the data are skewed towards lower scores.
Every chart has Download PNG and Download SVG buttons under it, so you can save the image for a report, an essay or a slide. Charts follow your light or dark theme on the page, and the saved image keeps its colours.
Reading the shape
| Shape | Meaning |
|---|---|
| Symmetric and bell-shaped | Roughly normal. Mean and median are close. |
| Long tail to the right | Positively skewed. The mean is larger than the median. |
| Long tail to the left | Negatively skewed. The mean is smaller than the median. |
| Two peaks | Possibly two groups mixed together. |
| Flat | Values are spread evenly. |
Choosing the number of bars
- Too few bars hide the shape, and too many make it jagged.
- Sturges’ rule suggests ⌈log₂(n)⌉ + 1 bars: 7 for 40 values.
- A round bar width, such as 5 or 10, makes the labels easy to read.
Each bar includes its left edge and leaves out its right edge, except the last bar, which includes both. A histogram is not the same as a bar chart: its bars touch because the data are continuous. For categories, use the bar chart maker.
How to cite this page
CalcPulse. (2026). Histogram Maker. https://calcpulse.com/histogram-maker/
Frequently asked questions
How do I make a histogram?
Enter your data, and choose a bar width or number of bars. The tool counts the values in each bar and draws the chart.
How many bars should a histogram have?
Sturges' rule gives ⌈log₂(n)⌉ + 1. A round bar width, such as 5 or 10, often reads better.
What is the difference between a histogram and a bar chart?
A histogram shows how numeric data are distributed in ranges, and its bars touch. A bar chart compares separate categories.
What is a relative frequency?
The share of all values that fall in a bar, shown as a percentage.
Can I download the histogram?
Yes. Use the PNG or SVG button under the chart.
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