Spaceflight launches and events database.
Launch Library 2 API is a free Science & Math API that requires no API key, is served over HTTPS and supports CORS, so it can be called from the browser.
A group of space enthusiast developers working on services to improve accessibility of spaceflight information.
Details from thespacedevs.com.

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ISRO Space Crafts Information
The Launch Library 2 API is provided by TheSpaceDevs (thespacedevs.com). A group of space enthusiast developers working on services to improve accessibility of spaceflight information.
Yes. The Launch Library 2 API is listed in the Science & Math 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 Launch Library 2 API requires no authentication, so you can start making requests without signing up.
Yes. The Launch Library 2 API supports CORS, so front-end JavaScript can call it directly.
Yes. The Launch Library 2 API is served over HTTPS, so it's safe to use in production.