pdflayer - Free, powerful HTML to PDF API supporting both URL and raw HTML conversion. Unlimited document size, lightning-fast and compatible PHP, Python, Ruby, etc.

Tesseract - Tesseract is an optical character recognition engine for various operating systems

Doczilla - Effortlessly create stunning PDFs and screenshots. Seamlessly store them in your own AWS or Google Cloud Storage bucket, putting the control and creativity right at your fingertips.

Onlineocr.net - Free Online OCR service allows you to convert PDF document to MS Word file, scanned images to editable text formats and extract text from JPEG/TIFF/BMP files

PDFCrowd - Pdfcrowd is a Web/HTML to PDF online service. Convert HTML to PDF online in the browser or in your PHP, Python, Ruby, .NET, Java apps via the REST API.

Prizmo - Prizmo is a scanning application for Mac with Optical Character Recognition (OCR) in over 40 languages with powerful editing capability, text-to-speech, and iCloud support.