---
title: "Histogram Maker - Frequency Distribution"
description: "Make a histogram online from pasted numbers or a CSV column. Compare automatic bins, frequency, density, and cumulative views, then export PNG, SVG, or CSV."
url: https://candoya.com/tools/histogram-maker/
locale: en
type: browser-tool
---

# Free Histogram Maker

Category: [Developer](https://candoya.com/tools/dev/)

## What does a histogram maker do?

A histogram maker groups numeric observations into equal-width intervals called bins, then draws touching bars to show the shape of the distribution. Paste values or import a CSV column, choose automatic or manual bins, and inspect frequency, density, cumulative values, and summary statistics without sending your data to a server.

This tool is for continuous numeric observations such as test scores, response times, measurements, and prices. Unlike a general bar chart, a histogram places values on a number line and uses adjacent bars because each bin covers a continuous interval.

The table lists every bin boundary along with count, relative frequency, probability density, and cumulative percent. Download it as CSV for further analysis, save a ready-to-share PNG, or keep the chart as a scalable SVG.

## How to use it

1. **Add observations** - Paste numeric values separated by commas, spaces, semicolons, or lines, or upload a CSV or TSV file and select a numeric column.
2. **Choose the bins** - Use Freedman-Diaconis for a robust automatic width, compare Sturges or square-root, or set an exact number of bins.
3. **Change the scale** - View raw frequency, relative frequency, probability density, or cumulative percent while the histogram updates live.
4. **Inspect and export** - Review summary statistics and exact bin values, then copy or download the table and save the chart as PNG or SVG.

## Who it's for

- **Students and teachers** checking the spread and shape of scores or measurements.
- **Analysts** exploring response times, prices, or quality-control readings before deeper modeling.
- **Researchers** comparing how automatic bin rules change the visible distribution.
- **Spreadsheet users** turning one numeric CSV column into a chart and auditable frequency table.

## Expert note

Bin choice changes the story a histogram appears to tell. Freedman-Diaconis uses the interquartile range, so it is less sensitive to extreme values than a standard-deviation-based rule. Compare at least two settings before calling a dataset unimodal, skewed, or unusually spread out.

## Frequently asked questions

### Is my histogram data uploaded?

No. Parsing, binning, statistics, chart rendering, and export happen in your browser. The numeric values and CSV contents are not sent to CanDoYa or stored in an account.

### Is the histogram maker free?

Yes. You can paste values, import a numeric CSV column, compare binning methods, change the bar scale, and export the chart or table without paying or signing up.

### How much data can I use?

The tool accepts up to 100,000 numeric values and files up to 5 MB. The chart supports at most 100 bins so axes and the frequency table stay usable on ordinary browsers and mobile devices.

### How are histogram bins chosen automatically?

The default Freedman-Diaconis rule estimates bin width from the interquartile range and sample size. Sturges uses 1 plus the base-2 logarithm of the sample size, while square-root uses the rounded-up square root of the sample count.

### What happens to a value on a bin boundary?

Each value goes into the interval that starts at its boundary. Bins include the lower endpoint and exclude the upper endpoint, except the final bin, which includes the dataset maximum so no observation is lost.

### What is the difference between frequency and density?

Frequency is the number of observations in a bin. Relative frequency divides that count by the sample size. Probability density divides relative frequency by bin width, so the total area of all bars equals one.

### Can I make a cumulative histogram?

Yes. Choose cumulative percent to make each bar show the share of observations at or below that bin's upper boundary. The last bar will equal 100 percent.

## Related tools

- [Chart Maker](https://candoya.com/tools/chart-maker/)
- [CSV to Chart](https://candoya.com/tools/csv-to-chart/)
- [CSV Statistics](https://candoya.com/tools/csv-statistics/)
- [CSV Viewer](https://candoya.com/tools/csv-viewer/)
- [Pivot Table](https://candoya.com/tools/pivot-table/)

---

*Markdown edition of <https://candoya.com/tools/histogram-maker/>, published for AI agents and other automated readers. Index of key pages: <https://candoya.com/llms.txt>.*