How to Sign a Photo or Image on iPhone and Android

“Signing an image” can mean two things: putting your signature on a photo of a document (a form you photographed, a screenshot, a scan) so you can send it back, or adding your signature to a photo or artwork you made. Both take less than a minute. Here is how, on every device.

Sign a photo on iPhone

The Markup tool in the Photos app has the same signature feature as Files and Mail.

1. Open the photo or screenshot in Photos and tap Edit.
2. Tap the Markup button (a pen tip) at the top.
3. Tap + and choose Add Signature. Pick a saved signature or create one with your finger.
4. Drag it into place and resize it with the corner handles.
5. Tap Done, then Done again to save.

Photos keeps the original: you can always go back with Edit → Revert.

Sign a photo on Android

Google Photos can draw on any picture:

1. Open the photo in Google Photos and tap Edit.
2. Choose Markup, pick the pen and a color, and write your signature with your finger.
3. Tap Done and save a copy.

This draws a new signature each time. For a reusable signature that looks the same on every document, use a signing app.

Sign a photo with Signature Maker (iPhone and Android)

The Signature Maker app treats images exactly like PDFs:

1. Create your signature once: draw it, type it or scan your real signature from paper.
2. Tap + next to Documents and choose Pick from Gallery.
3. Open the photo, tap Add Signature, drag and resize it.
4. Tap Save Document, then save the signed image or share it.

This is the easiest way to sign a photo of a paper form: photograph the form flat and in good light, sign the photo in the app, and send it back without ever printing it.

Tip for documents: if you need to send the signed form as a PDF, sign the photo and then, on iPhone, open the result, tap Share → Print, and use the share button in the print preview to save it as a PDF.

Sign a photo on a computer

• Mac: open the image in Preview, click the Markup button, then the Sign button, and place your signature. See how to sign a PDF on Mac; it works the same for JPG and PNG files.
• Windows or any computer: make a transparent signature PNG in the online generator, then add it on top of the photo in any editor that supports layers, or insert both into a Word or Google Docs file.

Signing your artwork or photography

Artists and photographers often sign digital work with the same mark every time. The cleanest way:

1. Make your signature once as a transparent PNG, typed in a calligraphy font or drawn with a stylus in the generator. Our signature styles guide has ideas.
2. Keep a black version and make a white one by inverting it in your image editor, so it works on both light and dark images.
3. Place it as a separate layer in your editor, in a corner, at about 3–5% of the image width, and lower its opacity slightly.

A consistent, layered signature is easy to resize for prints and social media, and it is harder to crop out than a watermark in the middle of the picture.

Frequently asked questions

How do I put my signature on a picture?

On iPhone, open the picture in Photos, tap Edit → Markup → + → Add Signature. On Android, use Google Photos’ Markup pen or an app like Signature Maker, which places a saved signature on any image from your gallery.

Can I sign a JPG file?

Yes. JPG and PNG images can be signed with iPhone Markup, Preview on Mac, Google Photos on Android, or Signature Maker on iPhone and Android.

Is signing a photo of a document legally valid?

For most everyday documents, yes. A signature added to a photo or scan is an electronic signature, recognised under the US ESIGN Act and EU eIDAS. Check whether the recipient accepts images or needs a PDF, and whether the document requires a wet-ink or notarised signature.

How do I sign a screenshot?

Take the screenshot, tap the preview that appears (iPhone) or open it in Photos, then use Markup → + → Add Signature. On Android, open it in Google Photos and use Markup, or sign it in Signature Maker via Pick from Gallery.