Reflow PDF for E-readers & Phones

Re-wrap scanned book pages to fit Kindle / Boox / phone screens - no OCR errors, all local

Reading an A4 scanned book on a 6-inch Kindle or a phone means endless zooming and panning. This tool detects every text line on the page, cuts lines at whitespace gaps, and re-wraps the pieces to the width of your target screen - producing a new PDF where each page exactly fills the small screen with text magnified 1.5-3x.

Unlike PDF-to-EPUB conversion, this is pure image processing: no OCR is involved, so what you read is the original book’s glyphs - zero recognition errors, which matters for serious reading. Cuts only happen in the whitespace between characters (pitch-aware for CJK, word gaps for Latin text), and figures are kept as whole blocks.

Built-in presets for 6" / 7" / 7.8" e-readers and phones, with adjustable text magnification, header/footer cropping (to drop page numbers), page ranges, and a live preview. Like every tool on this site, everything runs locally in your browser - your file is never uploaded. Think of it as a browser-based alternative to K2pdfopt.

How to use

Open the PDF you want to reflow (scanned or text-based)
Choose the target device (6" Kindle, 7.8" Boox, phone, etc.) and magnification
Fine-tune header/footer cropping with the live preview
Click "Reflow & download", then send the PDF to your device

FAQ

Will it introduce OCR errors?

No. Reflow is a pure image operation: text lines are detected, cut at whitespace gaps, and re-assembled. You always see the original scanned glyphs - there is no text recognition step, so there is nothing to get wrong.

What layouts are supported?

Single-column printed books work best (novels, textbooks, paper bodies). Multi-column pages (sidebars, two-column papers) and vertical CJK text are detected automatically and kept as whole pages instead of being reflowed, so reading order is never scrambled. You can also skip such pages with a page range.

How is this different from K2pdfopt?

Same idea (image-based line re-wrapping), but K2pdfopt is a command-line desktop program. This runs in your browser with live preview, and your file never leaves your computer.

How do I get the result onto my Kindle or Boox?

For Kindle use Send to Kindle (web or email). For Android-based readers like Boox, copy via USB or any cloud drive - the output is a standard PDF that opens in any reader.