Guides and practical checks

RedactNinja resources

Choose a task below for a worked explanation, the limitations to expect and checks to make before you share the result.

Everyday PDF tasks

Why Word to PDF changes your formatting

Check fonts, tables, images and page breaks when converting DOCX files in your browser.

Compress a PDF without losing readability

A measured fictional compression example, with settings and checks for small text and image quality.

Why you cannot select text in a PDF

Identify scanned pages, use OCR and check the recognised text before relying on search.

Combine and split PDFs in the right order

Assemble a report and appendices, then check page order, orientation and output boundaries.

PDF signature images and certificate signatures explained

Understand visible signature marks, certificate checks and the effect of changing a signed document.

SAR and redaction

How to redact a PDF properly

Understand why covering text is not redaction, then check your exported PDF before disclosure.

Redact student names in bulk using a CSV

Import known names, protect approved keep-visible terms and review ambiguous initials in the SAR workspace.

Troubleshooting

Troubleshoot PDF conversion and export problems

Practical checks for password prompts, missing content, failed processing and incomplete downloads.

PDF privacy and formats explained

Is it safe to upload PDFs to online converters?

Online PDF converters are convenient, and many are run responsibly. Whether one is safe for a particular document depends on what is in the file, what the provider does with it, and the rules you work under. This article explains what to check.

What PDF passwords do and do not protect

A password on a PDF can mean two quite different things. One keeps people out of the document altogether; the other only asks software to limit what people do once they are in. Knowing which you have helps you decide whether it is enough.

PDF/A explained: when you need an archive copy

PDF/A is a version of PDF designed for long-term storage. If an archive, court, university or records team asks for it, an ordinary PDF may be refused. This article explains what PDF/A is, how to tell whether a file conforms, and what RedactNinja's Prepare PDF/A does.

PDF to Word in Microsoft 365 compared with a browser tool

If you have Microsoft 365, Word can open a PDF and turn it into an editable document. A browser tool such as RedactNinja PDF takes a different approach. Neither copies a PDF perfectly, and they differ in what they keep and where the work happens.

Step-by-step PDF guides

Hands-on guides on RedactNinja PDF, the free browser PDF toolkit.

How to make a PDF smaller for email

If a PDF is too big to attach, you have two options: make it smaller with Compress PDF, or split it into several files that each fit under the limit. This guide shows both, with a measured example.

How to remove hidden data from a PDF before sending it

A PDF can carry more than you see on the page: author names, attached files, scripts, comments, text under black boxes and hidden layers. This guide shows how to find each one and remove it from the copy you send.

How to combine scanned pages into one PDF

Scanners and phones often save each page as its own image. This guide shows how to put those pages into one PDF in the right order, straighten them, make the text searchable and keep the file a sensible size.

How to sign a PDF without printing it

You do not need to print, sign and scan a document to put your signature on it. This guide shows how to add a visible signature to a PDF in your browser, how to reuse it, and when a certificate signature is the better choice.

How to password protect a PDF

A password on a PDF means the file cannot be opened without it. This guide shows how to add one with RedactNinja PDF, what the protection does, and how to share the password safely.

How to check that your PDF is not uploaded

Watch the browser network panel, read the security policy and try a tool offline.

Photos and screenshots

Image tools on RedactNinja Image, which runs in your browser.

Choose the right tool for your image

Background, file size, shape, format or privacy: which image tool to use, and what to check before you share the result.

Remove the background from an image

Cut out a person, pet or product and save it as a transparent PNG, on a plain colour or on a blurred background.

Remove EXIF and location data from a photo

See the GPS position, camera and dates a photo carries, then save a copy without them.

Blur faces and details in a photo

Find faces automatically, then pixelate, blur or cover them, along with number plates and name badges.

Convert HEIC to JPG

Turn iPhone photos into JPG files that open on Windows and every website, without uploading them.

Annotate a screenshot

Add arrows, boxes, highlights and numbered steps, and cover passwords or email addresses before sharing.

Compress an image

Make JPG, PNG and WebP files smaller, or under a set size for a form or email.

Convert an image to text

Copy the text out of a screenshot, a photo of a document or a scanned page.

How to check that your image is not uploaded

Watch the browser network panel and try a tool with the internet switched off.

SAR reference and product help

These resources cover the wider disclosure process and product controls.

Privacy, support and limitations

Use the security model and privacy notice to understand local processing and this public website's separate advertising arrangements. For a problem not covered here, contact RedactNinja without sending sensitive source records.

Examples are fictional. Guides do not replace a disclosure decision, legal advice or a check of your own output.