Guides for private PDF work

How to process a large PDF without uploading it

Open, compress, merge and export a large PDF in your browser without uploading it — with the documents we actually watched finish.

How to compress a 100MB PDF locally

Shrink a 100MB-plus PDF in your browser with no upload — and the measured reason the same file gives three different results in three browsers.

How to OCR a large scanned PDF without freezing

Make a 100-page scan searchable in your browser — with the measured per-browser timings, the live page counter, and how far off Firefox is.

Why browser PDF tools freeze on large files

The measured cause is not a slow processor: it is how much of the document an operation holds, and how long it waits before painting anything.

Large PDFs on desktop vs mobile — what we measured

Both phones we tested finished the same 119MB job the desktop did, slower. The measured rows, the bounds, and everything nobody has instrumented.

How to cancel a PDF operation safely

What Stop actually does in a browser PDF tool: which tools stop where, what the message means, and why nothing in the product claims to resume.

How UnboundPDF handles large PDFs locally

What runs where, why big documents are hard, and the 2026-08-15 benchmark tables across three browser engines — including the parts we could not measure.

How to edit text in a PDF — change existing text and keep the same font

Edit existing text in a PDF online, free, and keep the same font. Click a paragraph, retype, save — processed in your browser, not uploaded.

How PDF editors keep the same font — or quietly fake it

Same font after editing a PDF: what’s technically real, what’s a lookalike, and how to test any editor’s claim in two minutes.

Why can’t I edit text in my PDF? The 7 real reasons

The 7 real reasons PDF text won’t edit — measured across a 36-document test corpus — and the fix for each.

How to edit text in a scanned PDF — with local OCR

Edit text in a scanned PDF: local OCR in your browser recognises the words, you retype them, and the fix saves as real searchable text. No upload.

Adding text vs editing existing text in a PDF — two different jobs

Type-over tools vs true text editing: what each actually does to your PDF, how to tell them apart in two clicks, and when each is the right choice.

Can the old text be recovered after you edit a PDF?

Whether old PDF text survives an edit depends on the save path. The three cases, a one-minute check for your own file, and what to use instead.

How to compress a PDF for email without wrecking quality

Fit a PDF under email limits free in your browser — Gmail allows 25MB, Outlook.com 25MB, desktop Outlook defaults to 20MB. No upload.

How to merge PDFs privately (no upload)

Combine PDFs in your browser — reorder pages, then download one file. Your documents never leave the device.

How to OCR a scanned PDF in your browser

Make a scanned PDF searchable and selectable with on-device OCR. Text stays on your machine.

How to extract images from a PDF without taking screenshots

Pull embedded photos and logos out of a PDF — not page screenshots. Free, in-browser, no upload.

Extract original embedded images vs converting PDF pages to JPG

Extract Images pulls source pictures from a PDF; PDF to JPG renders whole pages. Both run in your browser with no upload.

How to extract every image from a PDF at once

Pull all embedded pictures out of a PDF in one pass and download them as a ZIP — free, in-browser, no upload.

PDF Privacy Lab — prove no-upload with DevTools

How to prove, in two minutes with DevTools, that a PDF tool never uploads your document — and UnboundPDF's own dated results: zero document requests, offline completion, 124 cross-browser runs, outputs re-opened in an independent reader.

How to compress a PDF to 100KB (and when that's possible)

Get a PDF under 100KB free, in your browser, no upload. Real measured results, what reaches the target, and what cannot.

How to compress a PDF to 500KB without wrecking it

Shrink a PDF under 500KB free in your browser. Measured: a 784KB scan hit 418KB in Balanced, 238KB in Maximum — nothing uploaded.

How to compress a PDF to under 1MB

Get a PDF under 1MB free in your browser — no upload, no watermark. Measured results by document type, and the one mode to avoid on text.

How to compress a PDF to under 2MB

Fit a PDF under 2MB free in your browser: measured runs, the mode that keeps text selectable, and what to do when a file refuses.

How to compress a PDF for government portals (USCIS, visa and application systems)

Fit PDF uploads under government portal caps in your browser — USCIS documents a 12MB limit. No upload, stamps stay legible.

How to merge and compress PDFs on a Mac

Merge and compress PDFs on macOS free in your browser — no app to install, nothing uploaded. Works the same in Safari, Chrome and Firefox.

How to merge and compress PDFs on Windows 10 and 11

Combine and shrink PDFs on Windows 10 or 11 free in your browser — no software to install and no upload site. Works in Edge, Chrome and Firefox.

How to merge and compress a PDF on iPhone without an app

Combine and shrink PDFs on an iPhone in Safari — no app to install, nothing uploaded. Files open from the Files app and the work stays on the phone.

How to merge and compress a PDF on Android without an app

Merge and shrink PDFs on Android in Chrome — no app install, no upload. Pick files with the Android picker, process on the phone, save to Downloads.

How to extract text from a PDF — the four routes that actually work

Get text out of a PDF four ways: convert to Word, export tables to Excel, OCR a scan, or select and copy. Free, in your browser, no upload.

Why won’t my PDF open? Diagnose it, then repair it locally

A PDF that won’t open is usually truncated, locked, or badly viewed. Tell them apart, then repair it free in your browser — no upload, no watermark.

PDF opens blank: the five things that actually cause it

Blank PDF pages have five causes: a failed render, a damaged file, an odd scan, empty pages, or protection. Tell them apart, free in your browser.

Why is my PDF blurry — and which blur can actually be fixed

Four reasons a PDF looks blurry: low-resolution source, over-compression, zooming a scan, printing an image page. Which are fixable, and which aren't.

PDF fonts not displaying correctly — why the same file looks different on every machine

Why PDF fonts display wrong: embedding, subsets and viewer substitution — why a file renders differently on two machines, and how to lock its look.

PDF tools for students — assignments, thesis chapters and scanned readings

Free PDF tools for students: merge assignment parts, compress a thesis, OCR scanned readings. Everything runs in your browser, nothing uploaded.

PDF tools for teachers — worksheets, handouts and scanned homework

Free PDF tools for teachers: build handouts from photos, bundle grading packs, OCR scanned homework, lock worksheets — in your browser, no upload.

PDF tools for HR — CVs, contracts, onboarding packs and redaction

Free PDF tools for HR: redact personal data, strip metadata, build onboarding packs and collect signed forms — in your browser, nothing uploaded.

PDF tools for lawyers — contracts, exhibits, redaction and archival

Free PDF tools for legal work: redact properly, strip metadata, paginate exhibits, archive to PDF/A — processed in your browser, never uploaded.

PDF tools for real estate — listing packs, disclosures and deeds

Build listing packs, photo sheets, signed disclosures and searchable deeds in your browser. Free UnboundPDF tools — documents are not uploaded.

PDF tools for accountants — statements, invoices and year-end archives

Turn statements into a typed Excel workbook, assemble client packs and archive year-end files in your browser — no client data uploaded.

PDF tools for freelancers — proposals, contracts, invoices and portfolios

Sign contracts, assemble proposals, send invoices and watermark portfolio proofs in your browser. Free UnboundPDF tools — nothing is uploaded.

PDF tools for small business — quotes, invoices, staff forms and records

Send quotes and invoices, fill staff forms and keep customer records in your browser. Free UnboundPDF tools — no documents are uploaded to a server.

How to redact a PDF so the text is actually gone

Covering text with a black box does not remove it. Here’s how to redact a PDF so the text is actually deleted — and how to check for yourself.

How to split a PDF by its bookmarks or chapters

Split a PDF using its own bookmarks — pick a level, keep chapters whole, and nothing before the first bookmark gets lost.

How to OCR a PDF in more than 100 languages

Pick from 126 languages or let auto-detect find the right one. OCR runs on your device — the scan is never uploaded.

Why typed cells matter when you convert a PDF to Excel

A real .xlsx with numbers, dates and currency as typed cells you can sum — not a wall of text pretending to be a spreadsheet.

How to flatten annotations, comments and stamps into a PDF

Make comments, highlights, stamps and form fields a permanent part of the page. How flattening works, what it bakes in.

How to convert a document with Cyrillic or Greek text to PDF

Word-to-PDF converters that print question marks for Cyrillic or Greek have no glyphs for them. How UnboundPDF embeds a real font instead.

Passport photo sizes by country — and how to make one at home

Passport and ID photo sizes for the US, UK, EU/Schengen, India and China, with a step-by-step to make one in your browser at 300 or 600 DPI.

Remove the background from a portrait — in your browser, no upload

Cut a person out of a photo entirely in the browser — transparent PNG or a solid colour, no upload, model downloaded once. What it does well, and what it does not.

Remove a watermark from a PDF — when it is possible, and when it is not

How PDF watermarks are stored, which kinds can be removed cleanly, how to do it in your browser with verification on the output, and why flattened scans are refused.

Resize an image to a file size or pixel size — without guessing

How to resize a photo to exact pixels or a KB limit for an upload form, convert between JPG, PNG and WebP, and what happens to EXIF data — all on your device.

Bates numbering — what it is, the conventions, and how to stamp a production set

Bates numbering for discovery and document productions: prefixes, padding, continuous numbering across files, confidentiality lines, and a step-by-step in your browser with a CSV index.

Stamp exhibits for a filing — labels, cover sheets and an index, in batches

How to label exhibits consistently for court filings and depositions — lettered or numbered, with cover sheets and a CSV index — in your browser.

A redaction log you can hand over — every region, verified on the final bytes

How to produce a redaction log for a document production: per-region verification on the delivered file, SHA-256 of the documents examined, and what the log does and does not prove.

Is that redaction real? Check a redacted PDF for text still under the boxes

How to test whether a redaction actually removed the text: the four ways text hides under a black box, a two-minute check in your browser, and how to read the report.

Get the text out of a PDF — plain text or Markdown, in reading order

Export a PDF's text as .txt or Markdown in reading order — headings kept, page markers optional — in your browser. When to OCR first, and what columns and tables do.

Add running headers and footers to a PDF — titles, dates, page X of N, filenames

How to add running headers and footers to a PDF — document title, date, page X of N, filename — with a separate first page, in your browser.

Excel to PDF — what prints, what doesn't, and why that is the honest contract

Convert Excel to PDF in your browser: every sheet paginated with repeated headers, stored values printed — and an honest account of what is not drawn.

Markdown to PDF — including plain text, which is already valid Markdown

Paste Markdown or plain text and download a typeset PDF: headings become bookmarks, GFM tables and code blocks render, raw HTML prints and never runs.

HEIC to JPG or PDF — iPhone photos, decoded on your device

Convert HEIC iPhone photos to JPG, PNG or one PDF in your browser: decoded on your device, rotation applied, EXIF and GPS not carried into the output.

Email to PDF — archive an .eml as a clean, paginated record

Turn a saved .eml email into a clean paginated PDF in your browser: headers typeset, inline images kept, attachments listed, remote content never loaded.

Sanitize a PDF — see what it carries besides its pages, then strip what you choose

Check a PDF before sending: a findings report of metadata, comments, attachments, scripts and hidden text — strip what you tick, verified on the output.

Make a booklet from any PDF — imposition, the fold, and the printer settings

Turn any PDF into a print-ready booklet in your browser: pages imposed two-up, blanks stated, saddle-stitch signatures optional — print, flip short edge, fold.

Letterhead on any PDF — overlays, under versus over, and what covering is not

Put letterhead or a stamp on an existing PDF in your browser: overlay under or over, all pages or a range — and why covering is never removing.

Make a PDF form fillable — real fields, drawn where the blanks are

Turn a flat PDF into a fillable form in your browser: draw text fields, checkboxes and dropdowns, then read back the fields the saved file really carries.

Split a two-up book scan — one sheet, two pages, the line where you put it

Split 2-up book scans into single pages in your browser: a movable gutter line, right-to-left reading order supported, covers left whole — image pages out.

Remove blank pages from a scan — measured ink, and a review before anything goes

Find and remove scanner blank-backs in your browser: ink measured per page, percentages shown, review mandatory — nothing removed until you confirm.

Why in-browser PDF tools are faster — measured

Round-trip measurements: local processing vs upload–process–download, on real files.

Guided outcomes — pages that do the job and verify it

Merge and fit an application pack, hit an email cap, check and clean before sharing, sign and flatten — each one checks the file it produced.

Quick task recipes — the how-to index

One page per job, each done without uploading: merge, split, convert, protect and more.

UnboundPDF vs upload-based PDF sites

What “in your browser” actually means, and when a server tool still wins.