Verification API

Verify that a user controls the phone number they gave you. Bremlio sends a one-time passcode by SMS and checks the code they enter — two API calls, with expiry and attempt limits handled for you.

Bremlio's verification API (operated by Bremlio Ltd, UK) confirms a user is reachable at, and in possession of, a mobile number — the basis of phone verification, account verification and step-up checks. It's the same reliable send/verify flow as the OTP API, framed around verifying users.

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Two calls to verify a user

# 1. Send the passcode
curl -X POST "https://api.bremlio.com/v1/otp/send" \
  -H "X-Api-Key: YOUR_API_KEY" -H "Content-Type: application/json" \
  -d '{"to": "+447700900123"}'
# → {"verification_id": "…"}

# 2. Verify the code the user entered
curl -X POST "https://api.bremlio.com/v1/otp/verify" \
  -H "X-Api-Key: YOUR_API_KEY" -H "Content-Type: application/json" \
  -d '{"verification_id": "…", "code": "123456"}'
# → {"verified": true}

What's handled for you

• Code generation and SMS delivery to the UK mobile.
• Expiry, so stale codes can't be used.
• Attempt limits (brute-force protection) and single use after success.

Bremlio is UK-focused today (SMS and OTP); it does not currently offer voice or WhatsApp channels.

Pricing

Item	Cost
SMS to a UK mobile	4.65p
Monthly fee / contract	None — pay as you go
Free credits on signup	25
Minimum top-up	£10

See full pricing.

Frequently asked questions

What is a verification API?

An API that confirms a user controls a phone number by sending a one-time passcode over SMS and checking the code they enter. It's used for phone verification, account verification and step-up authentication.

How is it different from the OTP API?

It's the same send/verify flow — 'verification API' describes the use case (confirming a user), 'OTP API' describes the mechanism (one-time passcodes). Same two endpoints, same 4.65p per SMS.

What does it cost?

Each verification sends one SMS at 4.65p to a UK mobile, pay as you go, with 25 free credits on signup.

Is it suitable for 2FA?

Yes — the flow suits two-factor authentication, phone verification and passwordless login.

Related

OTP API · SMS verification · UK SMS API · Pricing · Developer docs