Loona Treemap Maker — Free Treemap Charts
Budgets, disk usage, portfolio weights: when there are many parts and the whole is fixed, a treemap shows every share at once — big parts big, small parts small.
How to use the Treemap Maker
- Type your labels and numbers into the grid, or paste CSV into the box below the chart and press Apply CSV.
- Adjust the title, legend and per-series colours until the chart reads clearly at a glance.
- Press Download chart as PNG and drop the image into your document, slides or post. Use Copy my data as CSV to save your figures for later.
How it works
Areas are value ÷ total × canvas area. The squarified algorithm places the largest rectangles first and keeps aspect ratios close to square, then labels each rectangle with its name and value when it is large enough to hold text. The chart is drawn by hand on an HTML canvas by Loona’s shared chart engine — no chart library and no server. Everything is computed locally, so your numbers never leave your device.
Worked example
A startup’s annual spend becomes one treemap: salaries dominate, tools are a sliver — the board sees the cost structure in five seconds.
Frequently Asked Questions
Are rectangle areas exact?
Yes — each rectangle’s area is precisely its share of the total; the layout only decides positions and shapes.
Why is a small rectangle unlabelled?
Rectangles too small for text skip the inside label; the value still counts in the total. Keep categories above ~2% of the total or group them as "Other".
Which series is used?
The first series, one rectangle per row.
Treemap or pie?
Treemaps handle many categories (10–20) far better than pies.