When you're setting up Brand Indicators for Message Identification, or BIMI, you're essentially creating a new DNS record for your domain. Like other email authentication standards such as DMARC or SPF, a BIMI record is a TXT record that contains specific, machine-readable instructions. These instructions are made up of tag-value pairs, and one of the most fundamental tags you'll encounter is the version tag, denoted as v=.
This tag is a mandatory component of any BIMI record. Its purpose is simple but critical: it tells the receiving mail server which version of the BIMI specification your record is compliant with. This ensures that email providers can correctly parse and validate your record. As standards evolve, versioning becomes crucial for maintaining backward compatibility and introducing new features without breaking existing implementations.
What is the correct value for the BIMI 'v=' tag?
The correct and only currently accepted value for the BIMI version tag is BIMI1. Your BIMI record must begin with v=BIMI1; for it to be considered valid by mail servers that support the standard.
The BIMI Group, the body that develops the standard, confirms that this is the correct format. Omitting this tag or using a different value will cause BIMI to fail.
BIMI record tags explained
A complete BIMI record includes a few key tags separated by semicolons. While the version tag is required, you'll need others to make it work. Here’s a quick breakdown:
- v=: The version tag. As we've covered, this must be set to BIMI1. It is mandatory.
- l=: The location tag. This must be a secure URL (HTTPS) pointing to your brand's logo. The logo itself must be in SVG format. This tag is also mandatory.
- a=: The authority tag. This points to your Verified Mark Certificate (VMC), which is evidence that you have the right to use the logo. This tag is optional, but required by major inbox providers like Gmail and Apple Mail to display your logo.
Putting it all together, a simple BIMI record with a VMC would look something like this:
v=BIMI1; l=https://media.example.com/logo.svg; a=https://media.example.com/vmc.pem;
In summary, the v=BIMI1 tag is a simple yet non-negotiable part of your BIMI setup. Getting it right is the first step to ensuring your logo gets the visibility it deserves in your customers' inboxes.
