Upload a CSV. Walk away with verified, scored leads.
Drop in a CSV and Sendbox maps the fields, checks every email address (sorting each into deliverable, undeliverable, risky, or unknown), assigns a confidence score, and flags catch-all domains along the way. Bad addresses never make it into a campaign.
Lambda Group
Leads
Email | Email Status | First Name | Last Name | Company | Job Title | Tags | |
|---|---|---|---|---|---|---|---|
marcus.chen@notion.so | Verified | Marcus | Chen | Notion | VP of Product | SaaSDecision Maker | |
sarah.kim@stripe.com | Verified | Sarah | Kim | Stripe | Head of Growth | Prospect | |
tom.bradley@linear.app | Risky | Tom | Bradley | Linear | Engineering Lead | SaaS | |
priya.patel@figma.io | Verified | Priya | Patel | Figma | Director of Marketing | SaaSWarm Lead | |
david.wu@vercel.com | Verified | David | Wu | Vercel | CTO | Decision Maker | |
info@acme-generic.net | Invalid | Alex | Turner | Acme Corp | Founder | Startup | |
james.w@linearapp.com | Verified | James | Wilson | Linear | VP Engineering | SaaS | |
aisha.o@segment.io | Not checked | Aisha | Okonkwo | Segment | Revenue Operations | RevOps | |
nina.r@hubspot.com | Verified | Nina | Ramirez | HubSpot | Sr. Account Executive | SaaSWarm Lead | |
kevin.l@dropbox.com | Verified | Kevin | Liu | Dropbox | VP of Partnerships | Decision Maker | |
rachel.m@asana.com | Risky | Rachel | Moore | Asana | Head of Sales | SaaS | |
ben.c@monday.com | Verified | Ben | Carter | Monday | Director of Growth | Prospect |
Clean lists in, no cleanup after
Upload a CSV and watch columns map to the right fields automatically — fix anything that needs it.
Every address gets checked — deliverable, undeliverable, risky, or unknown — so bad emails never reach a campaign.
Every email gets a confidence score, so risky or unknown addresses come with a real basis for the call you make.
Catch-all domains get flagged during import, since they accept every address but don't guarantee delivery.
One upload, a verified list
Drag and drop or browse for your CSV — Sendbox reads the columns and suggests how they should map.
Common fields like email, first name, and company map themselves automatically; adjust anything that's off.
Every email gets checked on the way in, sorted into deliverable, undeliverable, risky, or unknown, with a confidence score attached and catch-all domains flagged.
Grabbed a lead list at a conference? Upload it and let verification catch the bad addresses before they hit a campaign.
Bought a list somewhere else? Import it and Sendbox flags the undeliverable and risky addresses before you send anything.
Run any list through verification. Catch-all detection and confidence scores help you decide which leads are actually worth emailing.
Verification handled for you, not left to manual review
Confidence-scored verification on the way in
Most tools let you import a CSV and cross your fingers. Sendbox verifies every email during import — deliverable, undeliverable, risky, or unknown — and attaches a confidence score, flagging catch-all domains so you can decide how to handle them.
Four verification tiers, each with a confidence score
Every imported email lands in one of four categories — deliverable, undeliverable, risky, or unknown — each with a confidence score attached. Catch-all domains get flagged separately, since they'll accept any address without guaranteeing delivery.
Got questions? We've got answers.
Still stuck? Talk to us →Every email is checked and sorted into deliverable, undeliverable, risky, or unknown, each with a confidence score, and catch-all domains get flagged separately.
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