SaaS Sign-Up Use Case

Stop Fake Sign-Ups
at the Form

Disposable emails, invalid addresses, and free-tier abusers inflate your sign-up numbers and corrupt your funnel analytics. Block them at the point of registration — before they touch your database.

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15–30%

of SaaS sign-ups may use invalid/disposable addresses on high-volume acquisition channels

< 500ms

BounceZero API response time — invisible to users

800+

disposable email providers blocked

$0

cost per blocked fake sign-up vs. cost to serve it

What Fake Sign-Ups Cost Your SaaS

Free Tier Abuse

Users spin up multiple accounts with disposable emails to extend trials indefinitely. Each fake account consumes compute, storage, and onboarding automation spend.

Corrupted Funnel Analytics

Sign-up → activation → trial → paid conversion rates are meaningless when a portion of "sign-ups" were never real people. CAC and LTV models are understated.

Transactional Email Bounces

Your confirmation emails, onboarding sequences, and product updates bounce on invalid addresses — damaging your transactional domain reputation even when you're not doing marketing.

CS & Support Noise

Automated onboarding sequences fire for fake accounts. Support tickets get created. Welcome calls get booked. All waste operational resources.

Inflated MAU Counts

Fake accounts inflate monthly active user metrics until churn catches up. This distorts investor reporting, product analytics, and team decisions.

Compliance Risk

Storing email addresses you've never verified exposes you to GDPR data minimisation questions. Verification at point of capture is a clean compliance answer.

Three Integration Patterns for SaaS

Pick the pattern that fits your stack and risk tolerance.

Synchronous Block

Call the API on form submit, server-side. Return validation error immediately if the address is invalid or disposable. User sees the error before the form completes. Zero fake accounts enter your database.

Best for: High-value sign-up flows, paid trial starts, anything with free credits.

Async Flag & Gate

Accept the sign-up immediately, trigger verification in a background job. Hold access to core features (e.g., sending email, API keys) until verification passes. User gets a "check your email" gate.

Best for: High-volume consumer sign-ups where friction at the form is a concern.

Score & Tier

Accept all sign-ups but tag them with a verification score. Route high-confidence addresses to standard onboarding; low-confidence to a reduced-feature tier or additional verification step.

Best for: PLG products with network effects where blocking too aggressively has CAC cost.

Integrate in Under 10 Minutes

Server-side Node.js example — the API key never leaves your server.

// POST /register route — verify before creating user
async function verifyEmail(email) {
const res = await fetch('https://app.bouncezero.io/api/v1/verify', {
method: 'POST',
headers: { 'Authorization': 'Bearer ' + process.env.BOUNCEZERO_API_KEY, 'Content-Type': 'application/json' },
body: JSON.stringify({ email })
});
return res.json();
}
app.post('/register', async (req, res) => {
const { email } = req.body;
const result = await verifyEmail(email).catch(() => null); // fail open
if (result?.result === 'invalid')
return res.status(422).json({ error: 'Please enter a valid email address.' });
if (result?.is_disposable)
return res.status(422).json({ error: 'Please use your work or personal email.' });
// Proceed with user creation...
});

Full examples in Python, PHP, Go, Ruby, and Java available in the API docs.

SaaS Sign-Up Verification FAQ

Integrate in 10 Minutes, Protect Forever

100 free verifications monthly to test your integration. Full API access on free plan.

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Full integration guide: API Documentation

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