I work on OnePassApps, the team behind app.onepassapps.com. Our Email Signature Builder is free, needs no account, and never touches your mailbox - it only writes the markup. This is a look at the HTML it actually emits, because that markup is the part that has to survive a trip through Gmail, Outlook or Apple Mail.

The builder lives at app.onepassapps.com/apps/email-signature. It opens with example details already filled in, so you can read the output before you touch anything.

What the builder writes

With those examples untouched, the HTML source pane holds 944 characters. It is a single table element with role="presentation", every rule inline, no class attributes and no style block:

<table role="presentation" cellpadding="0" cellspacing="0" border="0" style="font-family:Arial,Helvetica,sans-serif;font-size:14px;line-height:22px;color:#252525;width:100%;max-width:600px;table-layout:fixed;">

One table, one row, one cell. That shape is the point: table-layout:fixed with a max-width of 600px is what keeps a signature from reflowing on a narrow phone screen, and inline styles are what survive clients that strip a style element.

The cell carries the layout choice:

<td style="border-left:3px solid #176b62;padding-left:14px;overflow-wrap:anywhere;word-break:break-word;">

And the content inside it is the name, the role with the company, the contact links and the closing line:

<strong style="font-size:18px;line-height:24px;color:#176b62;">Sam Taylor</strong> 
<span>Studio Director · North Studio</span> 
<a href="mailto:sam%40example.com" style="color:#176b62;text-decoration:underline;word-break:break-word;"> 
<a href="https://example.com/" style="color:#176b62;text-decoration:underline;word-break:break-word;">https://example.com</a> 
<span style="font-style:italic;">Thoughtful work. Clear communication.</span>

Four details in there are worth naming:

  • The mail link percent-encodes the at sign as %40 in the href, and the visible label stays the plain address.
  • The website href ends with a trailing slash. The visible text does not. The builder normalises the link target and leaves your label alone.
  • The job title and the company are joined with a middle dot in one span, so they share a line and one style.
  • The name is the only element at 18px. Everything else inherits the 14px table size.

The phone number sits between the mail link and the website link and is handled the same way, with a tel: href.

Classic versus Accent line

There are two layouts. Switching from Accent line to Classic drops the border-left and the padding-left from that one cell and changes nothing else in the document: the table attributes, the name, the role span, all three links, the colour and the plain-text version came out the same in both runs.

The accent colour shows up in three places at once - the border on the cell, the name, and every link - and all three carry the same hex value. The builder exposes it as a colour field with a hex value beside it.

The plain-text version is a separate document

The Plain text pane is 132 characters: six lines, no markup at all. It opens with the name and the role with the company:

Sam Taylor Studio Director · North Studio

and closes with the website and the closing line:

https://example.com Thoughtful work. Clear communication.

The two lines in between are the email address and the phone number, in that order. Same six fields, same order, same middle dot, no styles and no anchors. That is the version to paste into a client that will not take HTML, and it is why the builder keeps two outputs instead of deriving one from the other.

Getting it out

The export step offers three formats - Formatted, HTML file and Text file - and the buttons beside them are Copy plain text, Copy HTML source and Copy signature. The Formatted option is the one to paste into a mail client; the two file formats are for when clipboard access is blocked, and the builder tells you as much.

The app also carries the setup steps for Gmail on the web, in order: select Copy signature, then open Settings, See all settings, General, Signature, Create new, then paste, choose your signature defaults and select Save changes. Underneath that it says Menus vary by version, which is the honest warning - the path is for a current Gmail, not a promise about every client.

There is a preview with three tabs, Preview, Plain text and HTML source, plus a Light and Dark message background. The Dark background is not a dark-mode signature, and the app says so: Dark approximates how dark-mode mail apps recolour a message. Send yourself a test to be sure.

What it leaves out, in the builder's own words

The page is specific about the edges, and it is worth quoting them rather than paraphrasing:

  • Contact fields stay in tab memory and disappear on navigation or reload.
  • There are no remote images, tracking pixels, mailbox connections or automatic installation.
  • Mail clients may rewrite HTML or apply their own styles.

Nothing leaves this tab, and the plan block says Standard is free with no card required. The app itself never uses OnePassApps credits.

What I did not do

I did not paste the result into Gmail, Outlook or Apple Mail and compare the three renders, and I did not open the downloaded HTML file in a client. Clients rewrite HTML, so the preview here is an approximation of what lands in a real inbox, not a guarantee. The builder says to send yourself a test, and that is still the advice after reading all of this.

The step-by-step guide for the same app is at app.onepassapps.com/guides/email-signature.