Bar Chart Generator

Build vertical and horizontal bar charts with grouped/stacked options, axis labels, and export.

Tested tool guide Tested browser tools Checked August 16, 2026

What Bar Chart Generator does, with a checked example

Enter category names with one or more numeric series, choose vertical or horizontal orientation, and pick whether series sit side by side per category (grouped) or stack on top of each other (stacked). The tool scales bars to the data, adds axis labels and a legend when more than one series is present, and renders a chart you can export as an image. The detail people miss: switching from grouped to stacked changes what the value axis measures - from the single largest value to the summed category total - so a scale that fit grouped bars can clip stacked ones.

Worked example

A concrete input and expected output from the current implementation.

Input

Category,Series A,Series B
Q1,120,80
Q2,90,150 (stacked mode)

Expected output

Two stacked bars: Q1 reaches a total height of 200 (Series A fills 0-120, Series B stacks 120-200); Q2 reaches a total height of 240 (Series A fills 0-90, Series B stacks 90-240). The value axis scales to at least 240, the larger of the two category totals.

In stacked mode each category's series values are summed in entry order from the baseline, so bar height is a running total (120+80=200, 90+150=240), and the axis follows the tallest stack rather than the largest single value (150).

How the result is produced

Data entry and series mapping

Each row you enter becomes one category, shown as a label on the category axis; each column after the first becomes a series with its own color and a legend entry once a second series is present. A blank or non-numeric cell is read as zero rather than rejected, so a typo shrinks a bar or stack segment silently instead of producing an error.

Grouped vs stacked scaling

Grouped mode draws one bar per series per category, all against a single value axis scaled to the largest individual value in the whole dataset. Stacked mode instead sums each category's series in entry order into one bar, placing segments end to end from the baseline, and scales the axis to the largest category total rather than the largest single value.

Good uses

Comparing a handful of series, such as product lines, across categories like quarters, with grouped bars
Showing how a total splits into parts per category with stacked bars, such as budget by department
Producing a labeled chart image to drop into a slide deck or report without opening a spreadsheet program

Limits and checks

Stacked totals assume non-negative values - a negative entry in a stacked series sits below the baseline and throws off the running total for segments stacked above it.
The axis maximum is derived automatically from your data, so if you need round gridline numbers or a fixed ceiling, check what actually rendered rather than assuming a clean scale.
Switching orientation from vertical to horizontal swaps which axis carries categories and which carries values, which can change label rotation and truncation even though the underlying data hasn't changed.

Common questions

If I switch from grouped to stacked, do my bars change height even though the data is the same?

Yes. Grouped bars are each scaled against the largest single value in the data; stacked bars are scaled against the largest category total, the sum of that category's series. The same dataset can look shorter in grouped mode and taller in stacked mode because the axis maximum is different.

Can I have a different number of series values in different categories?

Enter a value for every category/series pair if you can - a missing cell is generally treated as zero rather than skipped, so it shows as a zero-height bar or stacked segment rather than an omitted category. Fill in explicit zeros if that's what you mean, so the chart reflects your intent rather than a gap in the data.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.