Email signature generator › Logo
Adding a logo to an email signature
A logo in a signature is an image the recipient's mail client downloads at the moment they open the message. Almost every problem follows from that one fact.
Your details
Layout
Logo or photo — optional
Drop an image here or click to choose
PNG or JPG, under 2 MB
or use a hosted image
Preview
Nothing is uploaded and nothing is stored. The image you drop stays in this browser.
The logo has to be hosted, not attached
Mail clients render <img src="https://…"> by fetching the file. So the
logo needs a permanent public URL. Where to put it:
- Your own website — best option. Upload to something like
/img/signature-logo.pngand it lasts as long as the site. - A CDN or object store — fine, and fast.
- Google Drive, Dropbox, OneDrive share links — these do not work. They return a viewer page, not an image, and mail clients show a broken box.
- An image-hosting site — works, but the logo dies when the host does or when the file is pruned for inactivity. Signatures outlive free image hosts.
Format and size
| Setting | Recommended | Why |
|---|---|---|
| Format | PNG with transparency | Works everywhere; transparency survives dark mode better than a white block |
| Avoid | SVG | Outlook and several mobile clients do not render it |
| Displayed size | 60–100 px wide | Larger competes with the message |
| Actual file | 2× the displayed size | Stays sharp on high-density screens |
| File weight | Under 50 KB | It downloads on every open |
| Attributes | width and height set explicitly |
Prevents layout jumping and Outlook resizing |
Always set alt text
When images are blocked — common in corporate mail and the default in several clients —
the alt text is all the recipient sees where the logo was. alt="Rivera Studio"
degrades gracefully; a missing alt leaves an empty box.
This is also the argument against a signature that is one big image: with images off, an image-only signature shows nothing at all.
Why the logo arrives as an attachment
Mostly Outlook, and it happens when the image was pasted into the editor rather than referenced by URL: Outlook then embeds it in the message and the recipient sees an attachment. Referencing a hosted URL avoids it. Note that some corporate mail gateways re-embed images regardless — that is outside your control.
Dark mode
Several clients invert light backgrounds, and a dark logo on transparency can become invisible. Two practical mitigations: use a logo with enough internal contrast to survive either background, or add a small light padding area inside the image itself. Full dark-mode switching in email relies on CSS that Outlook ignores, so it is not worth building for a signature.
Logo or photo?
One, never both. A company implies the logo; a solo consultant, agent or recruiter is often better served by a face, because being recognised is part of the job. Both together makes a signature feel like a business card someone over-designed.
From the makers of FreeSignature
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Frequently asked questions
Why does my email signature logo show as a broken image?
The URL is not a direct link to the image file — Google Drive and Dropbox share links are the usual culprits — or it is served over http on an https page. Open the URL in a private window: if the bare image does not appear, mail clients cannot load it either.
What size should an email signature logo be?
60 to 100 pixels wide as displayed, with the actual file at twice that for sharp rendering on high-density screens, and under 50 KB in weight.
Can I use an SVG logo in an email signature?
No. Outlook and several mobile clients do not render SVG. Export a PNG with transparency at twice the display size instead.
Why does my logo arrive as an attachment?
Because the image was embedded rather than linked. Host it at a public URL and reference it with an img tag, and Outlook will fetch it instead of attaching it.
Do I need alt text on a signature logo?
Yes. Many recipients have images blocked by default, and the alt text is the only thing they will see in place of the logo.