Caller ID API that blocks spam calls and turns them into revenue
Caller ID API for MVNOs, CPaaS, UCaaS and Voice AI. Block fraud and sell protection as a value-added service.
{
"phone": "+18885550147",
"reputation": "SPAM",
"is_spam": true,
"spam_score": 94,
"total_complaints": 87,
"complaints": [
{
"Subject": "Reducing your debt",
"ViolationDate": "2026-07-04"
}
]
}Trusted by teams at
Two ways it pays for itself
Cut what spam costs your platform, or sell protection to your customers. Most partners end up doing both.
Sell protection as a feature
MVNOs, CPaaS and UCaaS platforms resell spam protection and caller intelligence as a value-added service: a new revenue line that also keeps subscribers around longer.
Stop paying to answer spam
Voice AI platforms run call screening before agents pick up. Fraud never reaches the model, so LLM tokens and telephony minutes stop burning on callers who were never customers.
Building a call blocking app?
Mobile security vendors and MVNOs ship the call blocking SDK under their own brand as a paid tier. New ARPU, lower churn, and anonymous lookups on iOS and Android.
Four products. One data set.
A live Caller ID API, a spam number feed you host, a white-label SDK for your app, and a DID reputation monitor for your number inventory. Every one of them is built to be resold.
Caller ID API with live spam detection
One GET request returns a spam verdict with complaint evidence and the business behind the number, from 195 countries. CPaaS and UCaaS platforms resell it as a protection tier and raise ARPU while their users stop answering scams.
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Spam status
Score, reputation and complaint history per number, ready for spam call blocking.
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Business identity
Name, location and industry from 195 countries.
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Carrier data
Carrier, number type and portability, with optional HLR via the carrier lookup API.
{
"entity_type": "BUSINESS",
"reputation": "VERIFIED",
"is_spam": false,
"business_info": {
"business_name": "Google LLC",
"city": "Mountain View",
"country": "US",
"industry": "Internet Services"
}
}Spam phone number database feed
Every reported number from 195 countries, the last 15 days, hosted on your side. One flat fee, no per-lookup bill, zero latency. Block at the switch, run it as a dynamic do-not-originate list, and sell protection on top. See the spam phone number database.
60s
update cadence
Flat fee
for every use case
Call blocking SDK
Spam protection inside your own app in about 10 lines of code. MVNOs and security vendors sell it as a paid tier and lift ARPU. Lookups are anonymous on iOS and Android, so a subscriber call log can never leak on our side. See the call blocking SDK.
Swift
Java / Kotlin
Flutter
React Native
Asterisk
DID reputation monitoring API
One call checks a number against 12 reputation sources and returns which ones flagged it, so you know exactly who to contact for remediation. Wholesale carriers, CPaaS and UCaaS put it in their own dashboard as a paid feature. Nobody else does this natively from an API.
See the DID reputation monitoring API{
"spam": {
"callerapi": { "is_spam": true, "complaints_count": 12 },
// one key per source that flagged it
// clean sources are absent
}
}SIP Firewall
Drop fraud traffic at the network edge, before it touches your switch or your minutes. Works alongside the feed and the API.
Results we can show. Names we can't.
Spam protection is part of our customers' competitive edge, so deployments sit behind NDAs. Here is recent work, anonymized.
Tens of thousands of dollars in new value-added service revenue
MVNOs, UCaaS providers and platforms with marketplaces resell our spam protection and caller intelligence under their own brand, and keep the margin on every subscriber who upgrades.
A fraud campaign, stopped
A Voice AI CPaaS platform came under a coordinated fraud call campaign. Screening dropped it before it reached their agents or burned their minutes.
Robocalls blocked, under their brand
Niche MVNOs ship robocall blocking to subscribers under their own name, powered by the minute-fresh feed. We stay invisible.
195
countries of business caller data
30
countries of live fraud detection
60s
between blacklist updates
Meets your stack where it is
Turnkey integrations for GoHighLevel, Aircall and Dialpad, licensed directly with pricing scoped to your deployment.
Talk to sales
Aircall
Asterisk
Start at $25. Scale to billions of calls.
Self-serve Caller ID API plans with instant access. Volume, feed and SDK deals are negotiated directly.
See all Caller ID API pricing tiersBasic
$25/mo
- 5,000 lookups per month
- Spam detection and business caller ID
- No-code integrations
Passing 300,000 lookups a month?
Volume plans run from $1,000 per month up to 50M+ monthly lookups, priced per tier. Tell us your traffic and we quote the exact step.
Spam phone number database feed
The minute-fresh list for 195 countries, hosted on your side. One flat fee, no per-lookup charges, every use case included.
See the feedCall blocking SDK licensing
Flat fee, or per subscriber per month with active call blocking. Sell protection as a paid tier under your brand and keep the margin.
See the SDK
A note from the founder
I run CallerAPI hands-on. Every case above is real work I was personally in the room for, and every name is protected because our data is part of how those companies win. You get the same discretion.
If you sit anywhere in the call path, tell me what you are dealing with. You will talk to me directly, not a sales team.
Dmitry B.
Founder & CEO, CallerAPI
Common questions
Start blocking spam calls today
Grab an API key and make your first lookup in minutes, or run a free caller ID test on any number first.