Check the signature
In Gmail: Settings → Signature, then copy from the editor won't give you HTML — paste the signature into a sent message, Show original, and copy the HTML part. Or paste from the signature generator you used.
How it works
Parse
The HTML is measured in bytes and its text extracted. Every img and a tag is read for size, source, alt text and target.
Classify
Images are split into icons, photos and tracking pixels by dimensions and path. Links into own-domain, social, external and shortened.
Flag
Weight, pixels, banners, embedded images, disclaimers, external styles, shorteners, mismatched link text — each with why it costs you.
Trim
The notes say what to remove. A clean signature is name, role, one link and a number.
The signature is on every message
People audit the copy of a cold email and never look at the signature, but the signature is the one part of every send that is identical across the whole fleet — every inbox, every step, every reply. If it carries a tracking pixel, every reply in a thread loads it. If it is fourteen kilobytes of nested tables from a generator, every message is fourteen kilobytes heavier than it needs to be and a five-reply thread is clipped in Gmail. If it has a banner, every message looks like it came from a marketing department. Whatever is wrong with it is wrong at scale.
What a good one looks like
Name, a role or one-line description, one link, a phone number with a country code. Maybe a small logo. That is the signature of a person who writes their own email, which is what a cold email is trying to be. Two social links at most, and only if they are current. No disclaimer — it has no legal effect and it is the surest corporate-bulk marker there is. No booking-page button in the first touch; the ask belongs in the body, not the footer.
Signature tracking tools
Several products inject a tracking pixel and rewrite links in the signature so the sales team can see opens on replies. They are a bad trade for cold outreach: the pixel is a bulk-mail pattern, the rewritten links are on a shared domain the filter already knows, and the open data is worthless since Apple and Gmail started prefetching images. The tool flags both, and the fix is to turn the product off for outbound inboxes.
Images
Outlook blocks images from unknown senders by default, so the first impression of an image-heavy signature is a row of broken boxes. A single hosted logo or headshot, under 100 pixels, with alt text, degrades gracefully. Base64-embedded images do not: they inflate every message by their full size, some clients refuse them, and they are the easiest thing to spot in the size checker. Host the image on your own domain and reference it.
Frequently asked questions
Does my email signature affect deliverability?
Yes, on every message. Tracking pixels, heavy HTML, banners, shortened links and external domains in the signature are all evaluated by filters exactly as if they were in the body — because they are.
Should a cold email signature have an image?
One small logo or headshot at most, hosted on your domain with alt text. Banners and multiple images make a personal note look like a campaign.
Are signature tracking tools safe to use?
Not for outbound. They add a pixel and rewrite links on every message and reply, which is the pattern filters associate with bulk mail, and the open data is unreliable anyway.
How big should an HTML signature be?
Under 2 KB is easy for a hand-written one. Generator output runs 5–15 KB; anything over 8 KB is worth rebuilding by hand.
Should I include a legal disclaimer?
No. It has no legal force, adds weight, and marks the message as corporate bulk. Cold email has better ways to look legitimate.
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