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How to Blur or Black Out a Screenshot on iPhone

iPhone Markup has no blur tool. How to hide information in a screenshot safely, why the highlighter leaks, Clean Up limits, and real blur options.

6 min read
Muhammed BasilFounder & maker of Pizazoo

The iPhone's built-in Markup has no blur tool. The safe built-in way to hide something in a screenshot is to cover it with a shape filled with a solid color at full opacity, or with thick pen strokes at full opacity. Do not use the highlighter: it is see-through by design, and simple brightness edits can bring the text back.

If you want an actual blur or a clean black bar, you need an app or a browser tool. Either way, keep blur for things that are not truly secret.

Does the iPhone have a blur tool for screenshots?

No. In iOS 27, Markup offers drawing tools (Pen, Mono line, Marker, Pencil, Eraser, Lasso and Ruler) plus an Add menu for text, signatures, stickers and shapes. None of them blurs or pixelates. The Photos editor has no blur brush either. Its closest feature, Clean Up, is designed to remove objects, not to redact text (more on that below).

How do I black out text in a screenshot with Markup?

You can do this right after taking the screenshot, or later from Photos by opening the screenshot, tapping Edit, then the Markup button.

  • Tap the Markup button, then the Add button and Add Shape.
  • Choose the square and drag it over the text. Drag the dots on its outline to resize it.
  • In the Markup toolbar, set the fill color to black (or any solid color) and leave opacity at the maximum. Apple's guide confirms shapes have border color, border width, fill color and opacity options.
  • Add one shape for each item you are hiding, then tap Done.
  • Pinch to zoom in on the result. If you can still make out any letter shapes, the cover is not solid.

The pen works too. Tap the selected pen to choose the thickest line weight and drag the opacity slider all the way up, then cover the text completely. A filled shape is still cleaner, because its edges are exact and it cannot leave gaps between strokes.

Why is the highlighter not safe for redaction?

The highlighter (Apple's toolbar calls it the Marker) is meant to tint text, not hide it. Its strokes are translucent, and layering several passes only makes them look solid. AppleToolBox showed that raising Exposure, Brilliance and Shadows or lowering Contrast in the Photos editor can reveal text hidden with the default Marker, even after several passes.

The same risk applies to any pen stroke with reduced opacity. If the cover is not fully opaque, assume someone can read through it.

Can Photos Clean Up hide personal information?

Clean Up is an Apple Intelligence tool in Photos for iPhone 15 Pro, iPhone 15 Pro Max and iPhone 16 or later, introduced in iOS 18.1 and not available in every region. In iOS 27 you open a photo, tap Edit, then Tools > Clean Up, and tap, brush or circle what you want removed. Apple's iOS 18 guide notes that brushing over a person's face may blur it with a pixelated effect.

It is the wrong tool for redaction:

  • It is built to remove distracting objects from photos, and Apple says Apple Intelligence outputs may vary. Text can end up smudged rather than gone.
  • A pixelated face is a weak cover (see the security section below).
  • Older iPhones cannot use it at all.
  • Like every Photos edit, it can be undone in your library with Revert to Original.

That last point applies to Markup edits made in Photos too. When you share from Photos, the Options screen in the share sheet has an All Photos Data switch. Apple says it shares "the original file with edit history and metadata" (AirDrop only), so leave it off when you send a redacted screenshot.

How do I blur part of a screenshot on iPhone?

You need something beyond the built-in tools. Two options we build (disclosure: we make Pizazoo):

  • Pizazoo for iPhone and iPad is free on the App Store for iOS 17 or later. Its markup editor includes a Redact tool that can Blur an area or cover it with a Black Bar, alongside the pen, arrows, numbered steps, text, spotlight and crop. Open the screenshot in Pizazoo, tap the markup (pencil) button, choose Redact, pick a style and drag over the area.
  • The free Redact Screenshot web tool works in Safari with nothing to install. Choose the screenshot from your photo library, pick Blackout (safest), Pixelate (strong) or Blur (weakest), and drag over anything sensitive. An experimental auto-detect can find emails, phone numbers and long tokens for you. It exports a full-resolution PNG or copies the result, and the image never leaves your browser.

Working on a Mac instead? See how to redact screenshots on Mac.

Is blurring a screenshot safe enough?

Not for real secrets. Blur and pixelation keep some of the original information, and short, predictable strings such as card numbers, one-time codes and account IDs are the easiest to reconstruct. Security firm Bishop Fox released its Unredacter tool in 2022 to show that pixelated text can be reversed, and its policy is that black bars are the only secure way to redact text. That is why our own web tool labels blur as the weakest option.

A simple rule:

  • Passwords, API keys, card numbers, codes and addresses: use a solid black bar, or crop them out entirely.
  • Faces, names in a busy group chat, background details: blur is usually fine.
  • Before you share: zoom in and check the edges of every cover.
  • Afterwards: the unredacted original may still be in your photo library (and in iCloud, if you use iCloud Photos). Delete it if you no longer need it.

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