OCR text extraction from images and PDFs with a free tier.
OCR.Space API is a free Documents & Productivity API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Free OCR API. Code snippets for calling the REST API. The OCR API takes an image or multi-page PDF document as input.
Details from ocr.space.

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The OCR.Space API is provided by Free OCR API (ocr.space). Free OCR API. Code snippets for calling the REST API. The OCR API takes an image or multi-page PDF document as input.
Yes. The OCR.Space API is listed in the Documents & Productivity 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.
Yes. The OCR.Space API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the OCR.Space API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The OCR.Space API is served over HTTPS, so it's safe to use in production.