Animated Treemap Generator
Nested rectangles sized by value and grouped by category, so both the split and the items within it read from area alone. Export MP4, GIF, PNG or SVG.
Free to try · No design skills · Ready in about two minutes
Overview
What is a treemap?
A treemap is a part-to-whole chart that represents every item as a rectangle whose area is proportional to its value, with items that share a category grouped into the same coloured block so the category breakdown and the items inside each category are both visible at once.
It solves a problem a pie or donut chart runs into past a handful of slices: because a treemap uses area rather than angle, and nests related items together, it stays legible with far more items on screen than a pie chart could hold, while still making the biggest few items and the biggest few categories obvious at a glance without reading a single label.
It's the standard way to show a budget, a portfolio, or a market broken down two levels deep — category and item — in one computed layout. The trade-off is precision: comparing two similarly-sized rectangles by eye is harder than comparing two bars on a shared axis, so when the audience needs to rank items precisely rather than see the overall composition, a sorted bar chart is the better tool.
How it works
How a treemap works
Each row is one item with a value (its size) and a category (its group). Items sharing a category are grouped into the same column, sized by the category's total share of the whole; within a column, items stack by their own value.
Reochart pops each rectangle in with a subtle stagger, category by category, and shades items within a category by their relative size so the largest item in a group reads slightly bolder than the smallest.
Examples
Example treemaps
Real charts made in Reochart, each with its own data and theme. They animate automatically as you scroll.
Good fit
When to use a treemap
- ✓A budget or spend breakdown by category and line item
- ✓Portfolio composition by holding and sector
- ✓Market share by segment, with sub-items inside each segment
Reach for something else
When not to use a treemap
- ✕You need to rank items precisely, comparing two similarly-sized rectangles by eye is harder than comparing bars on a shared axis.
- ✕There's no natural two-level grouping (category + item), a simple bar or pie chart is more direct for a flat list.
- ✕You have very few items (2-3), the nested-rectangle layout adds visual complexity a simple bar chart wouldn't need.
- ✕The story is change over time, a treemap is a single snapshot with no time dimension.
Compare
Treemap vs other charts
Treemap vs the alternatives for composition.
| Chart type | Best for | Avoid when |
|---|---|---|
| Treemap | Two-level composition (category + item), many items | Precise ranking matters more than overall composition |
| Donut / pie | A simple one-level split, 3-6 categories | You have a second level (items within each category) |
| Stacked bar | Composition across categories or time, precisely | You want an at-a-glance "map" of the whole, not exact bars |
| Sorted bar chart | Ranking many items precisely | The category grouping and overall proportion is the point |
Your data
What data you need
One row per item: a name, the category it belongs to (colours and groups the block), and its size. Repeat a category across rows to group items under it. Up to 20 items.
| Item | Category | Value |
|---|---|---|
| Paid search | Paid | 180 |
| Paid social | Paid | 140 |
| SEO | Organic | 90 |
Step by step
How to make a treemap
Drop your numbers in, or import a CSV.
Choose the chart, theme and animation speed.
Tune colours, labels and add your brand.
Download MP4, GIF, PNG or SVG.
Best practices
Get it right
- ✓Keep to a handful of categories (3-5) so each colour stays distinct.
- ✓Cap the total items around 15-20 so rectangles stay big enough to label.
- ✓Sort items within a category by size so the biggest reads first.
- ✓Use it when both the category split AND the items within it matter — that's the format's whole advantage.
- ✕Use it for a flat list with no natural category grouping, a sorted bar chart is simpler.
- ✕Cram in 30+ items, the smallest rectangles become unlabelable slivers.
- ✕Rely on it when exact values need to be read precisely, area is harder to judge than bar length.
- ✕Use near-identical colours for adjacent categories, area alone won't separate them without colour contrast.
Watch out
Common mistakes to avoid
Past 20 or so items, the smallest rectangles shrink below a readable size. Group the long tail into an "Other" category.
Forcing a flat, ungrouped list into a treemap adds visual complexity a simple sorted bar chart wouldn't need. Only use a treemap when there's a genuine two-level structure.
Two rectangles that are close in area are hard to rank by eye. When exact ranking matters, pair the treemap with a table or switch to a bar chart.
Similar shades for neighbouring categories make the grouping hard to see. Pick a theme with clearly distinct hues for each category.
Why Reochart
Built for sharing, not just charting
- ✓No design skills required
- ✓Animated MP4 and GIF exports
- ✓PNG and scalable SVG too
- ✓Your brand colours and logo (Pro)
- ✓Paste from a sheet or import a CSV
- ✓Presentation and feed ready in minutes
FAQ
Frequently asked questions
What is a treemap?
A treemap is a part-to-whole chart that represents every item as a rectangle whose area is proportional to its value, with items that share a category grouped into the same coloured block so the category breakdown and the items inside each category are both visible at once. It solves a problem a pie or donut chart runs into past a handful of slices: because a treemap uses area rather than angle, and nests related items together, it stays legible with far more items on screen than a pie chart could hold, while still making the biggest few items and the biggest few categories obvious at a glance without reading a single label. It's the standard way to show a budget, a portfolio, or a market broken down two levels deep, category and item, in one static-feeling but fully computed layout.
What data do I need?
A label, a value (the size), and a category (the group) per row. Rows sharing a category are grouped and coloured together automatically.
How many items can I show?
Up to 20 items across a handful of categories before individual rectangles get too small to label. For a longer list, a horizontal bar chart or ranking chart reads more clearly.
Do all items need a category?
No — a row without a category becomes its own single-item group, coloured on its own. Mixing grouped and ungrouped items works fine.
Can I make it animated?
Yes. Charts animate by default, and you can export the animation as an MP4 or GIF, or grab a static PNG or SVG if you prefer.
Can I export as SVG?
Yes. Pro exports a crisp, scalable SVG vector, alongside MP4, GIF and PNG. Every export renders at 1080p.
Is Reochart free?
Yes. The free plan lets you make every chart type except the animated bar chart race, and export an animated MP4 with a small watermark, no card needed. Pro adds the bar chart race, removes the watermark, and adds GIF and SVG, your brand colours and logo, longer videos and CSV import.
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