How to Add an Email Signature in Gmail

Gmail supports rich HTML signatures with formatting, images, links, and social icons — with two important constraints: a 10,000-character limit on the total HTML, and no <style> blocks (all CSS must be inline). This guide walks through adding a signature on desktop and mobile.

Updated: March 2026·~3 min read·Works with: Gmail (personal and Workspace)

Quick Answer

Gmail Settings (gear) → See all settings → General → Signature → Create new → paste content → set default → Save Changes

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How to Add a Signature in Gmail (Desktop)

Open Gmail Settings

Click the gear icon in the top right of Gmail. Click See all settings.

Stay on the General Tab

The General tab opens by default. Scroll down until you see the Signature section (roughly two-thirds down the page).

Click Create New

Click the + Create new button. A dialog appears — type a name for this signature (e.g. your name or “Work”). Click Create.

Paste Your Signature

Click inside the large signature editing box. Press Ctrl+V (Windows) or Cmd+V (Mac) to paste. Gmail preserves HTML formatting including colors, fonts, images, and links from SignForge signatures.

Set as Default

Scroll down to Signature defaults. In the “For new emails use” dropdown, select your new signature. Optionally set one for “On reply/forward use” (many people choose a shorter signature here or “No signature” to reduce thread clutter).

Save Changes

Scroll to the very bottom of the Settings page and click Save Changes. Open a new compose window to confirm the signature appears.

How to Add a Signature in the Gmail Mobile App

Gmail mobile stores signatures separately from desktop. The mobile app only supports plain text signatures — rich HTML must be set up on desktop. The mobile signature applies when you compose or reply from the app.

Open Gmail App Settings

Tap the hamburger menu (three lines, top left) → scroll down → tap Settings.

Select Your Account

Tap the email account you want to configure.

Tap Mobile Signature

Scroll to Mobile Signature and tap it.

Type and Save

Type your plain-text signature. Keep it concise: name, title, company, phone. Tap OK.

Gmail Signature Technical Constraints

10,000-character limit

Gmail counts every character in your signature HTML including tags. Exceeding 10,000 characters causes silent truncation — no error, the signature is just cut off. SignForge signatures are typically 1,500–3,000 characters.

No <style> blocks

Gmail strips <style> elements. All CSS must be written as inline style attributes: style="color:#333;font-size:14px". CSS classes don't work.

Images must use hosted URLs

Gmail doesn't support base64-encoded inline images in signatures. Images must be hosted at a public HTTPS URL. Gmail may re-host them on its own CDN (lh3.googleusercontent.com) — this is normal.

No custom fonts

Google Fonts and other @font-face fonts cannot load in email. Use system fonts: Arial, Helvetica, sans-serif or Georgia, Times New Roman, serif.

Google Workspace Accounts: Additional Considerations

If your Gmail account is a Google Workspace (business) account, your administrator may have configured:

Org-wide footer

An admin-appended footer added to all outgoing emails server-side. It appears after your personal signature. You cannot edit or disable it.

Locked signature

Some admins enforce a standardized signature via Google Workspace settings. If your signature fields are greyed out, IT has locked them.

Troubleshooting: Signature Not Appearing

Signature not showing in new compose

Go to Settings > General > Signature defaults. Confirm a signature is selected for 'For new emails use'. If it shows '(No signature)', click the dropdown and select your signature, then Save Changes.

Signature disappears after saving

Gmail's signature editor auto-saves but the page setting requires clicking 'Save Changes' at the bottom of the General settings page. If you close the tab without clicking Save Changes, your signature is lost.

Signature truncated or cut off

Your HTML has exceeded 10,000 characters. Simplify the signature — remove unnecessary elements or shorten link display text.

Related Guides

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