Best Email Signature Generators
The meaningful differentiator between email signature generators is HTML output quality — specifically whether the tool produces table-based layouts with inline CSS. Outlook uses the Word rendering engine, which rejects CSS flexbox, CSS grid, and external stylesheets. A generator that outputs modern CSS produces signatures that look correct in the preview but break in Outlook. The tools below are assessed on this criterion alongside pricing and account requirements.
What to look for in a signature generator
- •Table-based HTML (not flexbox/grid) — required for Outlook
- •Inline CSS only (no <style> blocks) — required for Gmail
- •Hosted image URLs (no base64) — required for Gmail signatures
- •No account required to generate or copy HTML
- •Direct HTML export (not just 'install to Gmail' workflows)
Tool Comparison
SignForge
Generates signatures using table-based HTML with inline styles — the only format that renders correctly in all versions of Outlook and Gmail. No account required to build or copy the HTML. Direct copy-to-clipboard output. Signatures are typically 1,500–2,500 characters, well within Gmail's 10,000-character limit.
HubSpot Email Signature Generator
Free tier requires creating a HubSpot account (CRM signup). The generated signature HTML has varied across versions — some outputs use CSS classes that Outlook strips. The tool is maintained as a lead-generation asset for HubSpot's CRM, not as a standalone signature product. Verify the output HTML before deploying.
MySignature
Subscription-based. Produces quality HTML output with table layout. Includes cloud-hosted signature management so you can update a signature once and it propagates (for supported clients). Includes basic analytics (link clicks, opens). Worth it for teams managing multiple signatures centrally.
WiseStamp
Longer-established product with more template variety and social icon integrations. Supports promotional banners that rotate (for supported clients). Integrations with social platforms allow pulling in real-time LinkedIn info. More expensive than alternatives for individual use — better justified for marketing teams who use the banner and tracking features.
Newoldstamp
Focused on team and company-wide signature management. Central admin panel to update all employee signatures simultaneously. Supports Google Workspace integration (auto-installs signatures) and Microsoft 365. Designed for IT administrators managing 10+ users. Per-user pricing makes it expensive for individuals.
Exclaimer
Enterprise product that operates at the mail server level — signatures are appended by Microsoft 365 transport rules or Google Workspace routing rules, not by the email client. This means the signature appears consistently regardless of device or client, including mobile sends. The trade-off: the sender doesn't see the signature while composing. Requires IT/admin setup. Used by organisations with strict brand compliance requirements.
How to Test Any Signature Generator
Before committing to a tool, inspect the HTML output it produces:
Check for <style> blocks
View the raw HTML source. If you see a <style> element with CSS class definitions, those styles will be stripped by Gmail. The signature may look fine in preview but break when sent.
Check for flexbox or CSS grid
Search the HTML for 'display:flex', 'display:grid', or 'flex-direction'. If present, the layout will collapse in Outlook — columns stack vertically or disappear.
Send to an Outlook address
The most reliable test. Send the signature to a live Outlook.com address (create a free test account) and open it in the Outlook desktop app. If it renders correctly there, it will work everywhere.
Check image src attributes
Images should be served from HTTPS URLs, not base64 data URIs. Base64 images will be stripped by Gmail signatures.
Related Guides
Try SignForge Free
Table layout, inline CSS, no account required. Build and copy your signature in under 2 minutes.
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