How to use Mailto Link Builder

Type the recipient address, or several separated by commas.
Add an optional subject and message, and a cc or bcc only if that client should show them.
Select the action, then copy the finished link into an HTML page, an email or a document.
Open the copied link once in a mail client and check that each field arrived as typed.

Example: Mailto Link Builder

Make a contact link for a support address with a prepared subject and a short message.

You add

To: [email protected], Subject: Question about my order, Message: Hello, please check order 1234.

You get

mailto:[email protected]?subject=Question%20about%20my%20order&body=Hello%2C%20please%20check%20order%201234. with 1 recipient, an encoded subject and no message sent.

Supported inputs and limits

A link holds up to 20 recipients per field, a subject of 200 characters and a message of 2,000 characters, and each address needs one @ with a domain that contains a dot. Values are percent-encoded, so an &, ? or # typed into the subject or message stays part of the value instead of splitting the link. Cc and bcc are standard RFC 6068 header fields, and clients still differ in how far they honour them, so keep anyone essential in the To field or in the message. A bcc address is written into the link as plain text and is visible to anyone who reads the page source, so it is never a way to hide a recipient. A mailto link asks the device to open a mail client to compose a message. This page sends nothing, and a very long link can be cut short by the client or by the page holding it.

Where your input is processed

This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.

A mailto link depends on the visitor's mail client

A mailto link is handled by the operating system and whichever mail app is registered, so the same link can behave differently on a phone, on a laptop with two mail apps, or in a webmail-only setup. The address part is the most portable, the subject and body are widely supported, and cc and bcc are the least consistent between clients even though RFC 6068 lists them as header fields. Because a bcc address sits in the link as plain text, anyone reading the source of the page can see it, so leave bcc out of a published link when the recipient must stay private. Show the address as visible text as well as a link, so a visitor with no mail client can still read it and use it by hand.

RFC 6068: The mailto URI scheme

Questions about Mailto Link Builder

Does this send an email?

No. The page only builds the link text. Nothing is sent and no mail client opens from here. A message can only be composed after a visitor opens the finished link on a device with a mail client.

Why are my spaces written as %20?

A link cannot carry a raw space, so spaces and line breaks are percent-encoded, with a line break written as %0D%0A. The mail client decodes them again, so the subject and message read normally when the draft opens.

Why does bcc not appear in some clients?

Cc and bcc are standard mailto header fields, but clients differ in how far they honour them. A bcc address is also written in plain text inside the link, so anyone who reads the page source can see it. Test the link in the client you expect people to use, and keep essential recipients in the To field or the message.

Can I put a whole paragraph in the message field?

Yes, up to 2,000 characters with line breaks kept. Keep it to a couple of lines where you can, because a long link makes a long HTML attribute and some clients cut it off.

Project manager: Tony Hines · Content updated 29 September 2026 · Report a problem

Mailto Link Builder

Build mailto link controls