How accurate is browser-side OCR?

Print + clean handwriting: 85-95% accuracy. Cursive or messy handwriting: 50-70%. Math notation, complex tables, and 2-column layouts perform worst. Tesseract is the same engine used by many cloud OCR services — accuracy is comparable for clean inputs.

Why is it slower than online OCR services?

Browser-side processing uses your CPU; cloud services use GPU farms. For privacy this is the tradeoff. A 10-page document takes 1-3 minutes locally vs 5-15 seconds via a cloud service. The privacy gain is significant — your document never leaves your machine.

Why does the first run take longer?

The OCR language data (3-15 MB depending on language) is downloaded and cached. Subsequent runs in the same browser skip the download.

Can I OCR multi-language documents?

Pick the dominant language. Tesseract handles secondary languages reasonably but accuracy drops for non-primary scripts. Multi-language model packs exist but are large; we'll add them in a future update if there's demand.

File & Format Converters · Free tool

PDF OCR to Text

Extract text from scanned or handwritten PDFs entirely in your browser. Uses Tesseract.js — no upload, no API key, supports English, Spanish, French, German, Portuguese, Italian.

Updated May 2026

OCR language

Each language downloads ~3-15 MB of model data the first time. Cached afterward.

Upload PDF (browser-only — never uploaded anywhere)

Upload a PDF to begin

Works on scanned PDFs and photo-based documents. Pure-browser OCR; nothing leaves your device.

Runs entirely in your browser using tesseract.js + pdfjs-dist. No upload, no API. Print + clean handwriting OCR accuracy: 85–95%. Cursive or messy handwriting: 50–70%. Math notation, complex tables, and 2-column layouts perform worst.

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What it does

Extract text from scanned or handwritten PDFs entirely in your browser. Uses tesseract.js (the open-source Tesseract OCR engine compiled to JavaScript) plus pdfjs-dist for PDF rendering. Supports English, Spanish, French, German, Portuguese, and Italian.

When to use this vs our regular PDF to Text tool: regular extraction works only when text is selectable (text-based PDFs). For scanned documents, photographed receipts, or PDFs created from images, you need OCR — that’s this tool.

Embed this tool on your siteShow snippet

Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.

<iframe src="https://freetoolarena.com/embed/pdf-ocr-to-text" width="100%" height="720" frameborder="0" loading="lazy" title="PDF OCR to Text" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>

Embed docs →

How to use it

Pick the OCR language (defaults to English).
Upload your PDF — never leaves your device.
Wait while each page is rendered then OCR’d (5–15s per page typical).
Download as .txt or copy to clipboard.

Frequently asked questions

How accurate is browser-side OCR?: Print + clean handwriting: 85-95% accuracy. Cursive or messy handwriting: 50-70%. Math notation, complex tables, and 2-column layouts perform worst. Tesseract is the same engine used by many cloud OCR services — accuracy is comparable for clean inputs.
Why is it slower than online OCR services?: Browser-side processing uses your CPU; cloud services use GPU farms. For privacy this is the tradeoff. A 10-page document takes 1-3 minutes locally vs 5-15 seconds via a cloud service. The privacy gain is significant — your document never leaves your machine.
Why does the first run take longer?: The OCR language data (3-15 MB depending on language) is downloaded and cached. Subsequent runs in the same browser skip the download.
Can I OCR multi-language documents?: Pick the dominant language. Tesseract handles secondary languages reasonably but accuracy drops for non-primary scripts. Multi-language model packs exist but are large; we'll add them in a future update if there's demand.

Show the math + sources

Formula

For each PDF page: render with pdfjs-dist at 2× scale to a canvas. Pass the canvas to tesseract.js with the user-selected language model. Concatenate per-page output with '--- Page N ---' separators. All processing in-browser; no network calls after model download.

What this assumes

Tesseract OCR accuracy: 85-95% on print + clean handwriting, 50-70% on cursive or messy handwriting, lower on math notation, multi-column layouts, and complex tables. Models for each language are 3-15 MB each, downloaded once and cached in the browser. Performance is CPU-bound (typical 5-15 seconds per page on consumer hardware). For higher accuracy on scanned documents at scale, cloud OCR services with GPU acceleration outperform but require uploading.

Sources

Methodology last verified: 2026-05-03

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