Email & phone list cleaning
Validate an existing list before you send to it or dial it.
What the problem actually is
Lists decay. Addresses go dead, numbers get reassigned, and a send to a stale list damages sender reputation in a way that is slow and expensive to repair. The same is true of a dialler working numbers that were never allocated.
Signals that carry the weight here
Syntax, MX and — where the provider answers honestly — mailbox existence.
Addresses that were throwaway when captured are certainly dead now.
Numbering plans change; a number valid at capture may not be allocated today.
Where to start
strictness=1 (balanced) — Balanced. For list work, prefer the status and sub_status fields over the verdict — they tell you why to drop a record.
A defensible starting point, not a guarantee. Strictness moves the verdict thresholds only; the risk score itself never changes, so you can re-tune without re-scoring anything.
The call
# One record at a time; loop your list client-side. curl "https://www.layercall.com/v1/verify/email?email=$EMAIL" \ -H "X-Api-Key: YOUR_KEY"
1,000 lookups a month free, no card. Get an API key.
Questions
Is there a bulk or CSV endpoint?
Not yet — today you loop the list against the single-record endpoints, which is straightforward but means you handle concurrency and retries. A batch endpoint is on the roadmap. Saying so plainly is better than implying a capability that does not exist.