Chart image API: turn a URL into a PNG or SVG chart (bar, line, area, scatter, pie, donut, stacked).
ChartBytes API is a free Development API that requires no API key, is served over HTTPS and supports CORS, so it can be called from the browser.
Turn a URL into a chart image (PNG/SVG) for email, READMEs, Notion and reports. Free, no signup.
Details from chartbytes.meridian-digital.pro.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Live public web data as JSON: Google Search, Maps, News, Amazon, jobs, reviews & more, one API key
Yes. The ChartBytes API is listed in the Development category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
No. The ChartBytes API requires no authentication, so you can start making requests without signing up.
Yes. The ChartBytes API supports CORS, so front-end JavaScript can call it directly.
Yes. The ChartBytes API is served over HTTPS, so it's safe to use in production.