PDF editor

Add text, signatures, pictures and shapes to a PDF, white out or redact areas, fill its form fields, and rotate, duplicate, delete or crop pages in your browser. Existing text is not retyped.

A PDF page is a list of drawing instructions, not an editable paragraph, so this editor adds new objects on top of the original pages: text, a drawn, typed or uploaded signature image, pictures, whiteout, pen, highlighter, shapes, page numbers and a watermark. It also rotates, duplicates, deletes and crops pages and fills the document's own form fields. The original text, vectors and search stay as they were. It cannot retype existing text: you cover a word and type the new one, and only the Redact tool removes what lies underneath.

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Why editing a PDF means adding objects

Each PDF page has a content stream: commands that place glyphs at exact coordinates in a font, draw paths and paint images. There are no paragraphs to reflow, and an embedded font often holds only the glyphs the document already uses. That is why this editor does not retype existing lines; it writes new objects into the same page instead.

Every mark is stored as a fraction of the page (x = 0.5 is the middle) and written as a native PDF object on save: text with an embedded font, pen strokes and shapes as vector paths, pictures as image objects. Latin text uses the standard Helvetica font; for other characters the first save downloads Noto Sans CJK KR and embeds only the characters you typed.

Whiteout and Redact look alike but do different things. Whiteout paints a white rectangle; the words under it are still in the file and can be selected, copied and found by search. Redact turns that whole page into a JPEG image on save, so the covered content is really gone, and so is that page's selectable text.

Content stream: The drawing commands of one page: text runs at fixed positions, paths and images.
Whiteout: A white box drawn over the page. It hides, it does not delete.
Redact: Black box plus rasterising the page on save, so the covered content no longer exists in the file.
Form field: A fillable box defined by the PDF itself (AcroForm). The editor writes your values into it.
CropBox: The visible area of a page. Cropping changes it; content outside is hidden, not deleted.

Example: correcting a date on a one-page A4 invoice

The invoice says 2025 where it should say 2026. Two ways to fix it, and what ends up in the file:

Page size (A4)        595.28 × 841.89 pt  = 8.27 × 11.69 in
Whiteout over 2025    x 0.62, y 0.18  →  369 pt from the left, 152 pt from the top
New text 2026         Helvetica 16 pt, drawn on top of the white box
Copy the page text    2025 and 2026 are both still in the file
Redact instead        page saved as a 1697 × 2400 px JPEG (2400 ÷ 11.69 in ≈ 205 ppi), quality 0.8
                      2025 is removed; the page text is no longer selectable

Use whiteout plus text for a visible correction on a document that is not confidential. Use Redact when the old value must not be recoverable, and accept that the page becomes an image.

Check the result

Open the saved file in another PDF reader and search for a word from the original text: it should be found on every page that carries no redaction.
On a redacted page, try to select text or search for the covered word: nothing should be found. Under whiteout the word is still found, which is expected.
If you filled form fields, reopen the file: without "Lock the values on save" the fields stay editable; with it they become plain page content.
Check the page count and orientation after rotating, duplicating or deleting pages.

Troubleshooting

Symptom	Likely cause	How to check	Fix
Saving stops with a message about one character	The annotation fonts have no glyph for it (an emoji, for example)	The message names the character	Replace or remove it; Latin, Korean, Japanese and Chinese text are covered
The first save with Korean or Japanese text fails	The CJK font is downloaded from a CDN the first time it is needed, and the connection failed	The message says the annotation font cannot be downloaded	Reconnect and save again; Latin-only text needs no download
Copied text still contains the part you covered	Whiteout only paints over the content	Search the saved file for the covered word	Cover that area with Redact instead of whiteout
Filled values are missing in the preview	Form values are written into the PDF on save; the on-screen preview may not draw them	Open the saved file in a PDF reader	Check the saved file; tick "Lock the values on save" when nobody should change them later
A digital signature shows as invalid or is gone	Saving copies the pages into a new document, which breaks certificate signatures	Signature panel of your reader, before and after	Make every edit before the document is signed; the Sign tool here places a signature image, not a certificate
Bookmarks are gone	The saved PDF is rebuilt from its pages and the outline is not copied	Bookmarks panel of your reader	Keep the original for navigation, or add bookmarks again in a desktop editor

Other ways to do it

Option	When it is the better choice
The program that made the PDF (a word processor or layout app)	When the text itself has to change or reflow: edit the source and export a new PDF.
A desktop PDF editor that edits existing text	When you must retype lines in place and the document's fonts allow it. That is a different operation from adding objects.
Merge and reorder pages	When the job is only page order, rotation or combining files, with no marks at all.

What this page does not cover

Existing text cannot be retyped or reflowed, and scanned pages get no OCR.
The Sign tool places an image of a signature; it does not create a certificate-based digital signature, and existing ones are not preserved.
Redacted pages become images without selectable text; whiteout is not redaction.
One PDF is edited at a time, and bookmarks are not carried over.

Versions and sources

Checked in Nerulio's PDF browser suite (tests/pdf-browser.mjs) on a 320-page synthetic document in Chromium 153, Firefox 155 and WebKit 26.6: text, pen, rectangle and highlight marks are written as native objects, a pen stroke lands at its page position, rotation and crop boxes survive, and Korean and Japanese annotation text is searchable in the result. PDF.js 6.3.289 draws the pages and pdf-lib 1.17.1 writes the file. Arbitrary real-world PDFs are not covered by that suite.

PDF editor

Add text, signatures, pictures and shapes to a PDF, white out or redact areas, fill its form fields, and rotate, duplicate, delete or crop pages in your browser. Existing text is not retyped.

How it works

Open the source file
Choose the processing mode and settings
Run, inspect the result and download

Supported formats

PDF / JPG / PNG / WebP → PDF / JPG / PNG — Input decoding and output encoding depend on browser support.

What this tool does

Native page copying, range/group splitting, vector/text/image annotations, placement-aware image recompression, embedded TrueType glyph trimming and AES-256 password handling. Full-page raster compression is a separate option.

Implementation and verified quality

advanced · PDF worker / ranged PDF.js / native annotations. Quality qualification is in progress. Pro/Flagship quality has not been established.

Before you export

Preserve mode retains native text, search and vectors; signatures are not retained. Font trimming drops the outlines of glyphs the document does not draw, and grayscale and raster mode are irreversible — raster mode removes searchable text. A forgotten password cannot be recovered, and unknown passwords are never guessed. The writer still parses full documents in a Worker.

Frequently asked questions

What determines the supported size?

Actual device memory, storage and codec support. Tested examples are evidence, not a guarantee for every file.

Are my files uploaded?

This tool processes the files you open on your device without uploading them. Images you explicitly attach to community posts are uploaded separately. Optional engines and models are downloaded from third parties; those requests expose connection information such as your IP address.

Will my work be saved automatically?

No. Images and editing state stay in this tab; media output can use local temporary storage. Changing language preserves your work; reloading, closing the tab, or following a link to another page can clear it.