Compare two PDF documents side by side online for free. Highlight differences in text, images and layout. No login or software download required. PDFworld.
The tool extracts the text layer from both PDFs page-by-page using PDF.js, then runs a word/character-level diff algorithm. Added words are highlighted in green, deleted words in red, and unchanged text in grey.
The similarity score (0–100%) indicates how much of the text is identical between the two PDFs. 100% means the pages are identical. It is calculated per-page and averaged for the overall score.
The comparison is text-layer based. It correctly identifies changes in content regardless of font, size, or layout differences. Image-only changes (like a logo swap) are not detected.
No. Both PDFs are compared entirely in your browser. Your documents never leave your device.
Pages are compared by position. Extra pages in either document are shown as entirely added or entirely removed.
Scanned PDFs contain images, not text. Use the OCR tool on PDFworld first to extract the text, then compare.
While the diff is open, use ← / → arrow keys to navigate between pages. Use the Jump buttons to skip directly to the next or previous changed page.