Scanned Thai documents — official forms, contracts, certificates written in Thai script — can be converted to searchable PDFs with free OCR. Here is how to recognize Thai characters including vowels and tone marks from any scanned PDF.
Go to pdfeditor.onl/ocr-pdf. No sign-up needed. The Tesseract Thai language model runs in your browser and processes files locally.
Upload your scanned Thai document. Thai script has no word spaces and uses stacked vowel marks — a 300 DPI scan is important for reliable recognition.
Tip: Thai fonts printed in clear, high-contrast modern typefaces (such as those used in government documents) OCR much better than decorative or handwritten-style fonts.
Choose Thai (ภาษาไทย) from the language selector. This activates the Thai script recognition model including all 44 consonants, vowel forms, and 5 tone marks.
Check the text blocks carefully. Thai OCR accuracy is good for standard government and business documents. Complex stacked vowel combinations and certain rare characters may need manual correction.
Click Download PDF. The Thai text layer is embedded. You can now search the document in Thai using Ctrl+F in Chrome or Adobe Reader.
Yes. Tesseract handles mixed Thai-English documents. Select Thai as the primary language — the model also recognizes Latin characters embedded in Thai text.
For visual text extraction and general search, yes. For official identity verification purposes, always use the original document — OCR output is not an official record.