How to create signature in Gmail on Mac: step by step in your browser

Where Gmail signatures live on a Mac

Gmail on a Mac runs in your browser. Google's Gmail Help pages describe signatures in the web settings at mail.google.com. They do not describe a separate Gmail app for macOS, so the browser is where you work.

The signature setting belongs to the account you are signed in to. Check which account is open before you type anything. A signature set on one account does not change the others.

Apple's Mail app is a different story. It keeps its own signatures, and the section on Apple Mail later on this page explains the difference.

Prepare the text before you open Settings

Write the signature in a plain note first. Check the spelling of your name, title and company. Copy the phone number in the format you want people to see.

Write a signature people can read

A few lines are enough for most people. Use your name, your job title, one phone number and one link. Each extra line makes the message look heavier. Plain layouts are also easier to read on a phone.

For example, you might write Ana Reyes on the first line, Account Director at Acme Co. on the second, the phone number on the third, and one link last. That is enough for most business mail.

Set defaults for new mail and replies

Gmail lets you set a default signature for new emails and a separate default for replies. Both sit in the Signature section you used earlier. You can also choose a signature for one email while you write it.

A split works well for many people. Give new emails the full version with title, phone and a link. Give replies a short version with just your name, since the other person already has your details.

Keep more than one signature

Gmail allows more than one signature. A common setup has one for client work, one for internal mail and one plain version for quick notes. Give each a name you will recognize later.

To switch while you write, click the pen icon labeled Insert signature at the bottom of the compose window. Choose the version you want, and it goes into the message.

Choose the right sending address

Your signature should match the address you send from. The Send mail as drop-down sits above the signature box on the Settings page. Pick the address this signature belongs to.

Aliases cause most of the confusion. If the drop-down shows only your main address, the alias may not be listed yet. Open Accounts and Import settings, check the Send mail as list, and then return to the Signature section.

Format the text without breaking it

Bold, italics and underline use ⌘B, ⌘I and ⌘U once keyboard shortcuts are on. Select text and press ⌘K to add a link. Press ⌘\ to clear formatting from the selection.

Keep the design modest. One font and one accent color cover most signatures. Bright colors and mixed fonts can look odd on other screens.

If formatting does not stick, you may be in plain text mode. The troubleshooting list near the end shows how to turn it off.

Size your logo and check the character limit

Google suggests a signature image between 70 and 100 px high and 300 to 400 px wide. The hard maximum is 100 px high by 1000 px wide. A logo that is 90 px high and 360 px wide sits inside the suggested range.

Images count toward the 10,000 character limit. That is far more than a normal signature needs. Check the total after you add a picture, not before.

Resize the file before you upload it. Gmail's guidance says to resize the image if an error appears when you save.

Test before you rely on it

Open a new message and send it to a second account you own. Look at the signature on your desktop and on your phone. Then reply to a message in an existing thread and check that the reply default is right.

In long threads, the signature can sit below the trimmed part of the message. Scroll to the bottom and click Show trimmed content if it is missing.

Apple Mail signatures are a separate setting

Apple's Mail User Guide manages signatures inside the Mail app. Open Mail > Settings from the menu bar, select Signatures, and pick the account in the left list. Click the Add (+) button, name the signature, and type it in the preview column.

Apple's guide does not say whether those signatures reach Gmail on the web. Treat them as separate settings. If you want the same text in both, paste it into each one.

The guide's version selector lists macOS 27 Golden Gate, with earlier versions also listed. Menus can look slightly different on an older release.

Common mistakes people make

• Typing the signature and closing the tab before clicking Save Changes.
• Setting a signature on the wrong sending address.
• Adding a large photo, then hitting the 10,000 character limit.
• Expecting Apple Mail signatures to show up in Gmail on the web.
• Sharing a Drive image with the wrong access, so it shows as broken.

Each of these takes a minute to fix once you know where the setting lives. Most of them come from skipping the save or picking the wrong address.

Ask Lazur where each setting lives

Lazur is a voice assistant for the Mac. Hold ⌥ ⌘, which is Option and Command, and ask about anything on screen. Lazur answers out loud.

Ask where a control is, and Lazur draws a circle and a label around it. Ask how to do a task, and Lazur guides you one click at a time, waiting for each click.

Lazur does not click for you, and it does not type into Gmail or change your settings. You stay in control of every click, which suits a setting you change only once.

Next steps after your signature works

Once the signature works, check how you send. Gmail offers an undo option after you send. How to undo send in Gmail on Mac explains the steps for the browser and Apple Mail.

If you write a lot of mail, Lazur for Gmail on Mac covers voice help for replies. Review your signature every few months, and update the phone number first when it changes.