How do I make a simple histogram?

Paste your numbers in Values, select By count, and enter a whole number from 1 to 200 in How many. The chart automatically divides the data range into that many equal-width bins. Select By boundary to enter your own increasing boundaries instead, such as 0, 10, 20, 30. The Use buttons load worked examples, including 0, 1, 2 with boundaries 0, 1, 2, which produces counts of 1 and 2.

If a value sits exactly on a boundary, which bin does it go in?

Every bin holds values from its lower edge up to but not including its upper edge. The last bin also includes its upper edge. For boundaries 0, 10, 20, the intervals are [0, 10) and [10, 20], so exactly 10 goes into the second bin and exactly 20 stays in it too. These same intervals appear in the table and CSV.

How do I choose the number of bins?

Changing the bin count changes the detail shown, without changing the data. Try different counts and compare the intervals and counts in the table. When the intervals need specific meanings, such as score bands, use By boundary and type those boundaries directly.

Can I use class boundaries or ranges that are not all the same width?

Yes. By boundary accepts increasing boundaries such as 0, 10, 20, 50, 100. Each bar has its interval width, but its height shows a count, not a frequency density. With unequal widths, bar areas do not represent relative frequencies. Values outside your boundaries are reported as counts below or above the range. Very wide ranges that exceed browser number arithmetic, or boundaries too close to remain distinct, are refused.

How do I paste my data, including a spreadsheet column?

Paste raw numeric values separated by commas, semicolons, spaces, tabs or new lines. Decimals, negatives, a leading plus and exponent form such as 1e3 are accepted. Leave out spreadsheet headers and category labels. A comma always separates values, so type 1200 rather than 1,200. An invalid token stops the chart and is named instead of skipped. Up to 100,000 values and 200 bins are counted.

Can I make a histogram from a frequency table or grouped data?

This tool creates a frequency table from raw values; it does not accept an existing table of intervals and counts. Pasting those columns would treat each number as a separate observation. Custom boundaries control how raw observations are grouped, rather than importing already grouped totals.

Does it show relative frequency, cumulative frequency or a probability distribution?

The vertical axis and table show the count in each bin. There is no relative-frequency, cumulative-frequency or probability mode, and no theoretical distribution generator. The input must be observations, not probabilities or a mean and standard deviation alone. Mean, median and standard deviation are not calculated here.

Can I export the chart or the counts?

Copy CSV puts the interval, lower boundary, upper boundary and count on the clipboard. Intervals are quoted so their commas stay within one field. Download SVG saves a standalone vector chart with the boundary rule in its description. There is no direct PDF or ZIP export.

Is my data sent anywhere?

No. Parsing, counting and drawing happen in your browser, and the SVG file is built there too. Your numbers and bin settings are kept in this browser's local storage for your next visit when storage is available. They are not uploaded.

Histogram Maker

Make a free online histogram from a list of numbers. Choose equal-width bins by count or enter class boundaries for your own intervals, then inspect the chart and its frequency table. The counts redraw as you edit; nothing is uploaded and no account is needed.

Values0 values

Bins

How many

Histogramcounts appear here

Values: 0

Bins: 0

Minimum: none yet

Maximum: none yet

Paste numbers into the Values box to count them into bins.

Which side of a boundary. Every bin counts values from its lower edge up to but not including its upper edge. The last bin also includes its upper edge, so the largest value is counted. That is what the brackets mean: a bin is written [from, to) in the table and in the CSV, while the last one is written [from, to]. The SVG you download carries this rule in its description, so the file still says how its counts were made.

Twenty test scores, 5 binsequal width boundaries across the range
[58, 65.4) 2, [65.4, 72.8) 4, [72.8, 80.2) 5, and 2 more
0, 1, 2 with boundaries 0, 1, 2the maximum is kept by the last bin
[0, 1) 1, [1, 2] 2
One value, repeated four timesa span of zero still gets a bin
[3.5, 4.5] 4

Values can be separated by commas, spaces, tabs or new lines, so a column copied from a spreadsheet pastes straight in. Up to 100,000 values and 200 bins are counted, an entry that is not a number is named rather than skipped, and a value outside your own boundaries is reported rather than folded into an end bin. Your data and settings stay in this browser.

Accuracy. Exact counts under a stated rule: every bin holds values from its lower edge up to but not including its upper edge, and the last bin includes its upper edge so the largest value is counted. Change the bin boundaries and the counts change with them, which is why the table is shown beside the chart.

Common questions

How do I make a simple histogram?: Paste your numbers in Values, select By count, and enter a whole number from 1 to 200 in How many. The chart automatically divides the data range into that many equal-width bins. Select By boundary to enter your own increasing boundaries instead, such as 0, 10, 20, 30. The Use buttons load worked examples, including 0, 1, 2 with boundaries 0, 1, 2, which produces counts of 1 and 2.
If a value sits exactly on a boundary, which bin does it go in?: Every bin holds values from its lower edge up to but not including its upper edge. The last bin also includes its upper edge. For boundaries 0, 10, 20, the intervals are [0, 10) and [10, 20], so exactly 10 goes into the second bin and exactly 20 stays in it too. These same intervals appear in the table and CSV.
How do I choose the number of bins?: Changing the bin count changes the detail shown, without changing the data. Try different counts and compare the intervals and counts in the table. When the intervals need specific meanings, such as score bands, use By boundary and type those boundaries directly.
Can I use class boundaries or ranges that are not all the same width?: Yes. By boundary accepts increasing boundaries such as 0, 10, 20, 50, 100. Each bar has its interval width, but its height shows a count, not a frequency density. With unequal widths, bar areas do not represent relative frequencies. Values outside your boundaries are reported as counts below or above the range. Very wide ranges that exceed browser number arithmetic, or boundaries too close to remain distinct, are refused.
How do I paste my data, including a spreadsheet column?: Paste raw numeric values separated by commas, semicolons, spaces, tabs or new lines. Decimals, negatives, a leading plus and exponent form such as 1e3 are accepted. Leave out spreadsheet headers and category labels. A comma always separates values, so type 1200 rather than 1,200. An invalid token stops the chart and is named instead of skipped. Up to 100,000 values and 200 bins are counted.
Can I make a histogram from a frequency table or grouped data?: This tool creates a frequency table from raw values; it does not accept an existing table of intervals and counts. Pasting those columns would treat each number as a separate observation. Custom boundaries control how raw observations are grouped, rather than importing already grouped totals.
Does it show relative frequency, cumulative frequency or a probability distribution?: The vertical axis and table show the count in each bin. There is no relative-frequency, cumulative-frequency or probability mode, and no theoretical distribution generator. The input must be observations, not probabilities or a mean and standard deviation alone. Mean, median and standard deviation are not calculated here.
Can I export the chart or the counts?: Copy CSV puts the interval, lower boundary, upper boundary and count on the clipboard. Intervals are quoted so their commas stay within one field. Download SVG saves a standalone vector chart with the boundary rule in its description. There is no direct PDF or ZIP export.
Is my data sent anywhere?: No. Parsing, counting and drawing happen in your browser, and the SVG file is built there too. Your numbers and bin settings are kept in this browser's local storage for your next visit when storage is available. They are not uploaded.

Exact counts under a stated rule: every bin holds values from its lower edge up to but not including its upper edge, and the last bin includes its upper edge so the largest value is counted. Change the bin boundaries and the counts change with them, which is why the table is shown beside the chart.