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BIMI(Brand Indicators for Message Identification)

A standard that displays your brand logo next to emails in supporting inboxes.

Definition

BIMI (Brand Indicators for Message Identification) is an email standard that allows senders to display their verified brand logo next to emails in the recipient's inbox. To use BIMI, you need a strong DMARC policy (quarantine or reject at 100%) and optionally a Verified Mark Certificate (VMC) from an authorized certificate authority. BIMI transforms the generic avatar or initial letter next to your emails into your recognizable brand logo.

Why It Matters

BIMI increases brand visibility and trust in the inbox. Studies show emails with BIMI logos have 10-20% higher open rates because recipients can instantly recognize and trust the sender. It is also a competitive differentiator that shows your brand takes email security seriously. In a crowded inbox, your logo makes your emails stand out.

How It Works

After setting up DMARC with a reject or quarantine policy at 100% enforcement, you create a square SVG logo file following BIMI specifications. Optionally, you obtain a VMC for Gmail. You publish a BIMI TXT record in DNS at 'default._bimi.yourdomain.com' pointing to your logo URL and VMC. When receiving servers verify your DMARC passes and find your BIMI record, they display your logo next to your emails.

Example

Here is a BIMI DNS record:

default._bimi.example.com TXT "v=BIMI1; l=https://example.com/bimi/logo.svg; a=https://example.com/bimi/certificate.pem"

Breaking it down:

  • l= points to your SVG logo hosted on your domain
  • a= points to your VMC (optional but required for Gmail)

When a Gmail user receives an email from example.com that passes DMARC, Gmail retrieves the logo from the URL and displays it as a verified sender avatar. Instead of seeing a generic "E" initial, the recipient sees your company's actual logo with a verification checkmark.

Best Practices

  • 1Ensure DMARC is at p=quarantine or p=reject with pct=100 first
  • 2Create a square SVG logo optimized for small display (ideally 32x32 pixels when rendered)
  • 3Host your logo on a reliable CDN for fast loading
  • 4Consider getting a Verified Mark Certificate for Gmail support
  • 5Test BIMI display in Gmail, Yahoo, and other supporting clients

Frequently Asked Questions

Gmail requires a VMC (Verified Mark Certificate) for BIMI display. Yahoo and some other providers show BIMI logos without VMC. VMCs require a registered trademark with a certificate authority like DigiCert or Entrust, costing around $1,000-1,500/year.

As of 2024, BIMI is supported by Gmail (with VMC), Yahoo Mail, AOL, Apple Mail (iOS 16+, macOS Ventura+), Fastmail, and several other providers. Coverage continues to grow as the standard gains adoption.

After setting up your BIMI record and meeting all requirements, it can take a few days to a few weeks for email providers to start displaying your logo. Gmail caches BIMI data, so changes may take time to propagate. Be patient and verify with test emails.