ProntoSignal · Pre-Verification Layer

Know the email
before you know the user.

Real-time email reputation scoring. Stop disposable addresses, breached accounts, and synthetic identities at the front door — before they ever touch your ID verification flow.

Under 400ms response
No PII retained
GDPR compliant
The Problem

Fraud starts
at the email field.

Document checks and biometrics are powerful — but expensive to run. And they happen too late. By the time a bot or fraudster reaches the ID upload screen, you've already spent on compute, API calls, and manual review queues.

Most bad actors arrive with a red flag you can see instantly: a disposable address, a breached domain, or an email registered two hours ago. ProntoSignal catches them before they cost you anything.

73% of onboarding fraud
starts with a disposable or recently-created email address.
$1.2M avg. annual loss
for mid-market platforms from synthetic identity attacks.
85% of blocked sessions
could have been filtered before a single Lambda invocation.
Example: Flagged sessions
Blocked
x7k2@mailinator.com
Disposable domain
4/100
user8842@tempr.email
Temporary provider
2/100
admin@newsite-xyz.ru
Domain age: 3 hours
7/100
test.user@10minutemail.com
Disposable + SMTP fail
1/100
How It Works

Six signals,
one risk score.

Every email is analysed across six independent vectors. The composite score drives your onboarding logic — fast-track, friction, or block.

Domain Analysis

Is the address from a known disposable, temporary, or throwaway provider? We maintain a continuously updated registry of 10,000+ disposable domains.

Mailinator · Tempr · 10MinuteMail

SMTP Handshake

A live, non-intrusive handshake with the destination mail server confirms the mailbox actually exists — without sending a single email.

MX lookup · RCPT TO check

Breach History

Cross-references the address against 12B+ credentials from major public breaches. A total absence of breach history on a "years-old" email is itself a signal.

HIBP · Public leak datasets

Social Footprint

Does the email resolve to any public professional or social presence? A connected footprint raises confidence; a ghost profile lowers it.

Professional · Public profiles

Blacklist Check

Is the sending domain or its upstream IP on active spam, malware, or scam blacklists? Ongoing abuse patterns surface here in near real-time.

Spamhaus · SURBL · URIBL

Domain Age & DNS

How old is the domain? Does it have healthy MX, SPF, and DMARC records? A 3-hour-old domain without proper mail setup is a near-certain fraud signal.

WHOIS · MX · SPF · DMARC
The Flow

Defence in depth,
without the latency.

ProntoSignal is the outer wall. ProntoID's document and biometric checks are the inner sanctum. Use them together to build a risk-based onboarding funnel that's fast for legit users and impenetrable for everyone else.

1

User enters email

At the very first touchpoint — signup form, checkout, age gate — the email is submitted. No UI delay, no extra screen.

2

ProntoSignal scores it

A single API call returns a 0–100 trust score with itemised signal breakdown. Typical round trip: 312ms. Your UX never feels it.

3

Route the session

Score ≥ 80: fast-track. Score 40–79: step up to biometric. Score < 40: block or queue for manual review. Your rules, our signal.

POST /v1/signal/email
// One call. Six signals. 312ms average.
{
  "email": "alex.chen@protonmail.com",
  "context": "signup"
}

// Response
{
  "score": 94,
  "verdict": "legit",
  "recommendation": "fast_track",
  "signals": {
    "disposable": "clean",
    "smtp_valid": true,
    "breach_count": 1,
    "blacklisted": false,
    "domain_age_years": 12,
    "social_footprint": "found"
  },
  "response_time_ms": 312
}
Use Cases

Where ProntoSignal
pays for itself.

RISK-BASED

Adaptive KYC Onboarding

Fast-track legitimate users straight to your product. Escalate high-risk emails into full biometric and document verification. Cut KYC costs by up to 60% without weakening compliance.

  • Tiered verification logic
  • Lower compute spend
  • Faster time-to-active
FRAUD PREVENTION

Synthetic Identity Defence

Block the bots and farm accounts at the front door. Catches the disposable-email patterns that fuel promo abuse, fake reviews, and loan fraud.

  • Pre-ID-gate filtering
  • Bot pattern detection
  • Blacklist-aware
DATING & SOCIAL

Know Your Pal Layer

Pair with KYP to give your dating users an extra layer of "is this person real?" — a matched social footprint raises trust before any ID is ever exchanged.

  • Social footprint signal
  • Trust tier assignment
  • KYP integration ready
AGE VERIFICATION

OSA Pre-Gate Filter

For Online Safety Act and adult-content platforms: filter obvious abuse attempts before burning age-estimation or document checks on throwaway sessions.

  • Cost-efficient screening
  • OSA workflow compatible
  • Pairs with Age Verification
E-COMMERCE

Checkout Fraud Shield

Stop card-testing and chargeback abuse at the checkout. Flag risky emails before the payment processor ever sees the transaction.

  • Pre-payment scoring
  • Chargeback reduction
  • Silent background check
PLATFORM TRUST

Marketplace Seller Vetting

Screen new sellers or hosts before they list. Combine with ProntoID document verification for a tiered trust model that scales with risk exposure.

  • Tiered seller tiers
  • Platform-wide signal
  • Combines with KYC
The Impact

Smaller fraud queue.
Lower compute bill.

By filtering obvious bad actors before they hit your ID verification pipeline, ProntoSignal reduces downstream load, shrinks manual review queues, and shortens time-to-active for genuine users.

Cut KYC Compute Costs by 60%
Filter throwaway addresses before they reach Textract or Rekognition
Slash Review Queue by 85%
Most manual review tickets come from obviously fake emails
Sub-400ms End-to-End
Signal check completes before the user has picked their password
Talk to Sales
Average Check Time
312ms
Disposable Domains Tracked
10,400+
Breached Credentials Indexed
12.3B
Signal Accuracy
98.7%
Frequently Asked

Everything you need
to decide.

ProntoSignal is an email reputation and risk-scoring API from ProntoID. It analyses an email address across domain reputation, SMTP validity, breach history, and known fraud patterns to produce a real-time trust score — before a user ever reaches document or biometric verification.
ProntoSignal cross-checks every address against a continuously updated registry of disposable and temporary email providers, performs a live SMTP handshake to confirm the mailbox exists, and evaluates domain age, MX record health, and blacklist status to flag throwaway addresses used by bots and fraudsters.
No. ProntoSignal follows the same zero-knowledge principle as the rest of the ProntoID platform. Only the resulting risk score and signal metadata are returned — the raw email address is not retained after the check completes.
Yes. ProntoSignal is a standalone pre-verification API. It works on its own as a low-friction fraud filter, or as the outer layer of a defence-in-depth flow that escalates risky sessions into full ProntoID document and biometric checks.
Typical response time is under 400 milliseconds. The check is designed to run silently in the background during signup, so users on the legitimate fast-path never notice it.
Yes. ProntoSignal is GDPR compliant by design — checks are transient, raw addresses are not persisted, data is processed in the EU, and the service inherits ProntoID's SOC 2 and ISO 27001 controls.
Pairs Well With

Layer the
ProntoID stack.

ProntoSignal is the outer wall. These are the services behind it.

DOCUMENT + BIOMETRIC

KYC for Businesses

Full identity verification with document authenticity and live biometric matching — the inner sanctum after ProntoSignal filters the queue.

Learn More
OSA COMPLIANT

Age Verification

UK Online Safety Act-ready age checks. Combine with ProntoSignal to filter obvious abuse before running full age estimation.

Learn More
DATING & SOCIAL

Know Your Pal

Peer-to-peer identity verification for dating apps. ProntoSignal's social footprint signal feeds directly into KYP trust tiers.

Learn More

Stop fraud before it
reaches your pipeline.

Add ProntoSignal to your signup flow in minutes. One API call, six signals, zero retention.

Get API Access Contact Sales

Free tier available  ·  No credit card  ·  1,000 checks/month