SendGrid Email Verification Integration

The integration imports contact lists from SendGrid into DeBounce for validation, then updates the list in SendGrid by unsubscribing the result categories you select, eliminating the need to export, upload, and re-import files manually.

• Pulls any SendGrid contact list into DeBounce with a single click. No CSV export is needed.
• Runs every address through multiple validation layers, including catch-all testing and spam-trap detection that SendGrid’s own checks don’t cover.
• Writes the outcome back to SendGrid by unsubscribing the result categories you select from that list.
• Leaves your original contact records intact. Selected addresses are unsubscribed from the list, not deleted from your SendGrid account.
• Disconnects cleanly when the job is done if you set it up for a one-off clean instead of ongoing use.

Three things need to be in place. The integration does not require SendGrid’s Pro or Premier tiers, which is the main practical difference between this route and SendGrid’s own validation product.

Five steps, from creating the key to suppressing bad addresses. Steps 1 and 2 are one-time setup. Steps 3 to 5 are what you repeat each time you clean a list.

Each address comes back with a numeric code and a text reason, in both the exported file and the API response. The codes tell you which categories are safe to keep in SendGrid and which to suppress before your next send.

Deciding what to do with accept-all and unknown results

Neither is automatically bad. If you send through a provider that expects a bounce rate below 4%, leave both out of the send. If you send from a dedicated server with your own IPs, they may be safe, depending on list health and on whether those contacts opted in themselves.

Accept-all domains are common in small businesses and in government, medical and educational organizations, where the addresses behind them are often genuine. Catch-all validation resolves them into valid or invalid at a stated 95% accuracy, for 10 credits per address rather than the standard 1.

Role accounts depend on source rather than the technical result. They are usually fine where you know the owners, and a poor idea where the address arrived through a registration form.

SendGrid applies its own suppression rules on top of anything you push across, which explains most cases of a message not sending after a clean.

• An address that bounces twice is logged to SendGrid’s bounce suppression list, and later sends to it are suppressed automatically.
• Unsubscribed recipients are tracked separately from bounces in SendGrid’s suppression system.
• Removing a recipient from the bounce list allows sending to it again, which matters after a temporary domain outage.

On thresholds, SendGrid recommends generating hard bounces from fewer than 5% of attempted messages. Most mailbox providers expect under 2%, so treat 2% as the working target.

SendGrid ships its own Email Address Validation, available to Email API Pro and Premier level accounts only. Below those tiers, the option to create a validation key does not appear at all, and it is API-only, with no interface for uploading a list.

On coverage, SendGrid returns Valid, Risky, or Invalid plus a score, backed by six checks: syntax, MX or A record, suspected disposable, suspected role, known bounces, and suspected bounces.

The two are not mutually exclusive. Pro and Premier teams often use SendGrid’s real-time endpoint at signup and run periodic list cleans through the integration.

Cleaning a list fixes the addresses already in it, not the ones arriving tomorrow. Around 30% of emails go bad within a single year, so validation at the point of capture does more long-term work than any single cleaning pass.

• The real-time validation widget adds validation to any web form with a single JavaScript snippet and no backend work. It checks formatting, disposable domains, mailbox existence, and typo domains as the visitor types.
• The email validation API suits backend integration, returning Safe to Send, Risky, Invalid, or Unknown with the numeric code, the reason, and a did_you_mean suggestion on typos.