NullSig

Professional Email Signature Generator by NullorNaN Systems

Free professional email signature generator

Create an HTML email signature for Outlook, Gmail, and Apple Mail. Choose from six executive themes (including a no-background option), preview it live, then copy or download it. No signup required.

Your details

Only your name is required. Anything you leave blank is left out of the signature.

Identity

Contact information

Any format. Include a + and country code for international numbers.

Links

Shown as a bold call to action.

Branding

Logo

A public https:// PNG or JPG. SVG doesn't display in Outlook or Gmail.

Digital business card

Scanning it with a phone camera offers to add you to contacts. The code is made in your browser. Your details aren't sent to NullSig.

Theme

Saved only in this browser's local storage. Nothing is sent to NullorNaN. Uncheck to erase.

Preview

Slate Blue · 540 px wide

This is an example. Enter your name to start your own signature.

On a light email background
On a dark email background
How to use
    View HTML source

    Need a hand with more than your signature?

    Building a startup without a CTO? NullorNaN gives founders senior technology leadership and hands-on engineering, a few hours a month.

    What are you working on? (optional)

    Null CXO

    Fractional CTO and CIO Leadership

    For organizations needing experienced technology leadership without a full-time executive commitment.

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    Principal Engineering

    For organizations needing experienced technical execution and architectural expertise.

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    Explore Engineering Services

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    Business & Technology Advisory

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    Startup & Founder Support

    For early-stage founders building or scaling technology-enabled businesses.

    • Fractional technical leadership
    • MVP architecture
    • Product and platform strategy
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    Book a free 30-minute call See current pricing

    How to add your signature

    Copy signature puts a formatted version on your clipboard that pastes directly into a signature editor. If pasting doesn't keep the formatting, use Download HTML, open the file in your browser, select the signature, copy it, and paste again.

    Outlook for Windows (classic)

    1. Select Copy signature above.
    2. In Outlook, go to File → Options → Mail → Signatures.
    3. Select New, name the signature, and paste into the edit box (Ctrl+V).
    4. Choose it as the default for new messages and replies, then select OK.

    Outlook on the web, new Outlook for Windows, and Outlook for Mac

    1. Select Copy signature above.
    2. Open Settings → Accounts → Signatures (on Mac: Outlook → Settings → Signatures).
    3. Create a new signature, paste it into the editor, and save.
    4. Set it as the default for new messages and replies.

    Gmail

    1. Select Copy signature above.
    2. In Gmail, open Settings (gear) → See all settings → General → Signature.
    3. Select Create new, name it, and paste into the signature box.
    4. Choose it under Signature defaults, then select Save Changes at the bottom of the page.

    Apple Mail on Mac

    1. Select Copy signature above.
    2. In Mail, open Mail → Settings → Signatures and pick your account.
    3. Select +, name the signature, and paste over the placeholder text.
    4. Clear "Always match my default message font" so the signature keeps its styling.

    Tip: send yourself a test email after saving the signature. Some clients, including Outlook for Windows, render HTML differently from a browser, and many hide remote images until the reader allows them.

    Questions

    Is NullSig really free?

    Yes. There is no account, payment, or email address required, and every theme and feature is available to everyone.

    Do you store what I type?

    No. Your signature is generated in your browser and is never sent to NullorNaN. If you check "Remember my details on this device", your details are saved only in this browser's local storage, and you can clear them at any time.

    Will it work in Outlook?

    The signature is built with tables and inline styles, the approach Outlook for Windows handles most reliably. Email clients differ, so send yourself a test message after you add it.

    Why isn't my logo showing?

    Logos must be a public https:// PNG or JPG. Outlook and Gmail don't display SVG images, and some email clients block remote images until the reader allows them.

    Does NullSig add anything to my signature?

    No. There are no tracking pixels, promotional links, or NullorNaN branding in your signature unless you add them yourself.