Match the provider, improve the placement
Sendbox figures out each recipient's email provider through domain lookup and MX records, then sends through a mailbox on that same provider, Gmail recipients get a Gmail sender, Outlook recipients get an Outlook sender. Gmail, Outlook, Yahoo, Apple, and custom domains are all supported.
ESP Matching
AI Features
Sendbox identifies the ESP
Domain lookup combined with MX record analysis works out whether a lead sits on Gmail, Outlook, Yahoo, Apple, or something custom.
- Provider detection via MX records
- Automatic matching
- Three modes
- Better inbox placement
A look inside the Sendbox dashboard, where ESP Matching lives.
Mailboxes
Email | Status | Sent / Limit | Tags | Warmup Stats | Warmup | Sending | |
|---|---|---|---|---|---|---|---|
jordan@brightloop.com Jordan Reyes | Active | 22/50 | Cold Outreach | Day 1920/3088% health | |||
maya@brightloop.com Maya Torres | Active | 27/50 | Cold Outreach | Day 1516/3082% health | |||
pool@deskflow.io Outbound Pool | Active | 6/20 | Warming Pool | Day 910/3071% health | |||
jordan@seconddesk.io Jordan (Domain B) | Active | 33/50 | Cold Outreach | Day 2223/3090% health | |||
team@coldrelay.com Growth Team | Active | 45/55 | Agency | Day 2727/3096% health | |||
leah@fourthdesk.io Leah Nakamura | Active | 14/45 | Cold Outreach | Day 1011/3075% health | |||
sam@outreach.agency Sam Whitfield | Active | 39/50 | Agency | Day 2323/3089% health | |||
maya@signalwarm.io Maya (Warm Pool) | Active | 4/20 | Warming Pool | Day 45/3060% health | |||
noah@fourthdesk.io Noah Bennett | Active | 31/50 | Cold Outreach | Day 1718/3085% health |
The right mailbox for every provider, every time
Provider detection via MX records
Gmail, Outlook, Yahoo, Apple, and custom providers all get detected automatically through domain lookup and MX analysis.
Automatic matching
In auto mode, every email routes through a sender on the same provider as the recipient.
Three modes
Disabled, auto, or custom rules with priority, pick whatever level of control fits your workflow.
Better inbox placement
Same-provider delivery improves the odds of landing in primary instead of spam or promotions.
Step 1
Sendbox identifies the ESP
Domain lookup combined with MX record analysis works out whether a lead sits on Gmail, Outlook, Yahoo, Apple, or something custom.
Step 2
Routes to a matching sender
A Gmail lead gets sent from one of your Gmail mailboxes, an Outlook lead from an Outlook mailbox, improving the odds of landing in the inbox.
Step 3
Pick your matching mode
Three options: disabled (no matching at all), auto (Sendbox handles it), or custom rules with priority settings for finer control.
Where it fits
Landing in the Gmail primary tab
Gmail-to-Gmail delivery tends to land in primary more consistently. ESP matching routes your Gmail leads through Gmail senders without you having to think about it.
Running mixed Gmail/Outlook campaigns
With both Gmail and Outlook mailboxes connected, ESP matching assigns each lead to the best-fit sender automatically.
Setting up custom routing
For advanced setups, write custom rules with priority to route specific domains through specific mailboxes with full control.
Sending that knows the provider, not a blind relay
Sending mailbox matched to inbox provider, automatically
Sendbox checks MX records to identify each recipient's email provider and routes the send through a matching mailbox, Gmail leads get a Gmail sender, Outlook leads get an Outlook sender. Pick disabled, automatic, or your own prioritized custom rules.
- Beats Smartlead
- Beats Lemlist
MX record detection across the major providers
Sendbox reads domain and MX records to identify Gmail, Outlook, Yahoo, Apple, and custom email providers.
- Matching runs automatically in auto mode, or you can define custom rules with your own priority settings.
It detects each recipient's email provider through domain lookup and MX records, then routes your email through a mailbox on that same provider, Gmail to Gmail, Outlook to Outlook.
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