Can I get a transparent PNG?
Not today. background only accepts a six-digit hex colour, and the chart is rendered onto it, so every PNG has a solid backdrop. Matching the background to your page is the closest equivalent.
A PNG chart generator with exact pixel sizes
Some destinations only take a raster image. Add format=png to any PlotLark request and the same configuration comes back as a PNG, rasterised on the server at precisely the width and height you asked for.
- format=png on any request
- 320–1600 × 240–1200 px
- Download without an account
URL
https://www.plotlark.com/api/chart?type=donut&title=Storage+by+workspace&labels=Design%2CEngineering%2CSupport%2CSales&values=42%2C96%2C18%2C27&width=900&height=520&color=%2370c9b0&background=%23fffdf8&grid=true&valuesOn=true&format=pngcURL
curl "https://www.plotlark.com/api/chart?type=donut&title=Storage+by+workspace&labels=Design%2CEngineering%2CSupport%2CSales&values=42%2C96%2C18%2C27&width=900&height=520&color=%2370c9b0&background=%23fffdf8&grid=true&valuesOn=true&format=png" --output chart.pngHTML
<img src="https://www.plotlark.com/api/chart?type=donut&title=Storage+by+workspace&labels=Design%2CEngineering%2CSupport%2CSales&values=42%2C96%2C18%2C27&width=900&height=520&color=%2370c9b0&background=%23fffdf8&grid=true&valuesOn=true&format=png" alt="Storage by workspace" width="900" height="520" />No account and no key needed for these requests. Swap /api/chart for / to reopen the same configuration in the studio.
Choosing PNG or SVG
The two formats come from one drawing, so they always show the same chart. Pick by where the image is going.
| Destination | Best format | Why |
|---|---|---|
| Email and chat | PNG | The widest client support for inline images, with no vector rendering differences. |
| Documents and PDFs | SVG | Text and shapes stay sharp when the page is zoomed or printed. |
| Slides and screenshots | PNG | Drops straight into tools that only accept a bitmap. |
| Web pages and READMEs | Either | SVG is smaller and sharper; PNG avoids sanitisers that strip inline SVG. |
Size and background behaviour
- Exact dimensions
- width and height accept 320–1600 and 240–1200 pixels. The PNG comes back at those numbers, so an <img> tag with matching width and height reserves the right space and avoids layout shift.
- Backgrounds are opaque
- background takes a six-digit hex colour and the PNG is drawn on it. Transparent PNG output is not supported today, so pick a background that matches the surface the chart will sit on.
- One resolution per request
- There is no retina multiplier. For a 2× asset, ask for twice the pixels and display it at half the size.
Two ways to produce the file
- From the studio
- Build the chart and press PNG. Your browser rasterises the preview at the reported pixel size and downloads it, with no account required.
- From the API
- Append format=png to a GET /api/chart request. The server rasterises the chart and answers with image/png, an ETag, and the same five-minute cache policy as SVG.
What PlotLark does not do
These limits apply before you start, so nothing on this page promises more than the renderer delivers.
- One non-negative numeric series per chart, from 1 to 12 points.
- Bar, line, area, and donut. No stacked, dual-axis, or time-series grammar.
- 320–1600 px wide and 240–1200 px tall, on a solid six-digit hex background.
- Anonymous rendering is capped at 60 origin requests a minute per address.
Common questions
How large can the PNG be?
Up to 1600 × 1200 pixels. Larger presets and retina multipliers are deliberately deferred until rendering cost has been measured.
Does the PNG look the same as the SVG?
Yes. Both formats come from one drawing pass, so the PNG is a rasterisation of the same chart rather than a separate layout.