Phone Verification

Detect SIM swaps, VOIP numbers, and phone fraud.

Overview

Phone verification provides:

• Carrier lookup - Who operates this number?
• Line type detection - Mobile, landline, or VOIP?
• SIM swap detection - Recent SIM changes?
• Port detection - Was the number ported?

Using Phone Verification

curl -X POST https://api.simplr-ai.com/v1/check \
  -H "X-API-Key: sk_live_xxxxx" \
  -d '{"phone": "+14155551234"}'

Phone Signals

Signal	Description	Risk Impact
recent_sim_swap	SIM changed in 7 days	Critical
line_type: voip	Virtual number	High
ported	Number transferred	Medium
carrier	Current carrier	Informational

SIM Swap Detection

SIM swaps are a major fraud vector for account takeover:

{
  "signals": {
    "phone": {
      "recent_sim_swap": true,
      "sim_swap_date": "2024-01-10T00:00:00Z",
      "days_since_swap": 5
    }
  },
  "risk_score": 85
}

Recommended Actions

Days Since Swap	Risk	Action
0-7	Critical	Block or strong verification
8-30	High	Additional verification
31-90	Medium	Monitor
90+	Low	Normal

VOIP Detection

VOIP numbers are often used for fraud:

{
  "signals": {
    "phone": {
      "line_type": "voip",
      "carrier": "Google Voice"
    }
  },
  "risk_score": 55
}

Best Practices

1. Check at login - Especially for 2FA
2. Block recent SIM swaps - For sensitive operations
3. Consider VOIP context - Some legitimate users use them
4. Report fraud outcomes - Help improve detection