Fidro Blog
Practical guides on fraud prevention, email validation, and chargeback protection for developers and product teams.
Tuning Fraud Thresholds: How to Balance Security and Conversion
Setting fraud thresholds too high blocks real customers. Setting them too low lets fraud through. Learn how to find the right balance using precision, recall, and iterative tuning with risk score data.
How to Block Disposable Emails in Laravel, Node.js, Python & PHP
Code examples for blocking throwaway email signups in every major framework. Laravel validation rules, Express middleware, Django validators, Flask decorators, and raw PHP -- all using one API.
Card Testing Attacks: How Fraudsters Validate Stolen Cards on Your Checkout
Card testing attacks let fraudsters validate thousands of stolen card numbers through your checkout. Learn how these attacks work, the warning signs to watch for, and how to stop them with velocity limits, IP intelligence, and risk scoring.
Account Takeover Prevention: A Developer's Guide
Account takeover attacks cost businesses $13 billion annually. Learn how ATOs work, the signals that indicate an attack, and how to build layered defenses using email, IP, and behavioral analysis.
Email Bounce Rate: What It Is, Why It Matters, and How to Fix It
High email bounce rates damage your sender reputation and reduce inbox placement. Learn what causes bounces, how to calculate your bounce rate, and practical steps to bring it under control.
How to Detect VPN and Proxy Users on Your Website
VPNs and proxies hide a user's real location and identity. Learn how VPN detection works, when to block VPN users, and how to implement IP intelligence in your application.
Geolocation Fraud Detection: How Location Data Catches Bad Transactions
IP geolocation reveals mismatches between where a customer says they are and where they actually are. Learn how location intelligence catches fraud that email and card checks miss.
How to Reduce Your Stripe Chargeback Rate Below 1%
Exceeding 1% chargeback rate triggers Visa and Mastercard monitoring programs with fines up to $25,000/month. Here's a practical checklist for keeping your rate well below the threshold.
What Are Disposable Emails and Why You Should Block Them
Disposable emails let users create throwaway inboxes that bypass your verification flows. Learn how they work, why they damage your business, and how to detect them in real time.
How Chargeback Fraud Works and How to Prevent It
Chargeback fraud costs merchants billions annually. Learn the mechanics of friendly fraud, first-party fraud, and true fraud — and the practical steps to prevent chargebacks before they happen.
Email Validation API Integration Guide: Best Practices for Developers
A practical guide to integrating email validation into your signup flow. Learn where to validate, how to handle edge cases, and the patterns that reduce fraud without hurting conversion rates.
How to Detect Disposable Emails in Your Signup Flow
A practical implementation guide for adding disposable email detection to your registration form. Covers API integration, response handling, user messaging, and the edge cases that trip up most implementations.
Free Email Providers vs Disposable Emails: What's the Difference?
Gmail, Yahoo, and Outlook are free but legitimate. Mailinator, Guerrilla Mail, and 10MinuteMail are disposable and risky. Learn how to tell them apart and why the distinction matters for fraud prevention.
Email Validation for SaaS: The Complete Guide
Everything SaaS teams need to know about email validation — from basic format checks to advanced disposable detection, risk scoring, and integration patterns that protect revenue without killing conversions.
The True Cost of Fake Signups: What We Found Analyzing 10,000 Accounts
We analyzed 10,000 SaaS signups to measure the real impact of fake accounts. The results: 23% used disposable emails, they cost 4.7x more in infrastructure per dollar of revenue, and they destroyed conversion metrics.
What Is a Risk Score? How Fraud Risk Scoring Works
A risk score is a numerical value that represents the likelihood a user or transaction is fraudulent. Learn how risk scores are calculated, what signals they incorporate, and how to use them in your application.
IP Intelligence: How to Detect VPNs, Proxies, and Tor at Signup
IP intelligence reveals whether users are masking their location with VPNs, proxies, or Tor. Learn how IP analysis works, when anonymization is a fraud signal, and how to use it without blocking legitimate users.
Free Tier Abuse: How to Protect Your SaaS Without Hurting Real Users
Free tiers drive growth but attract abuse. Learn how to detect multi-account fraud, disposable email signups, and resource exploitation while keeping the experience smooth for legitimate users.
Stripe Radar vs Custom Fraud Prevention: When You Need Both
Stripe Radar provides baseline fraud protection, but it has blind spots. Learn when Radar is sufficient, when you need additional fraud detection, and how to layer them effectively.
How to Fight a Stripe Chargeback (and Win)
A practical guide to responding to Stripe chargebacks with compelling evidence. Learn which dispute reasons you can win, what evidence to submit, and how to automate the process.
Pre-Transaction Fraud Detection: How to Catch Bad Actors Before Payment
Pre-transaction fraud detection evaluates risk signals before payment is processed. Learn why validating emails, IPs, and geolocation before checkout prevents chargebacks and saves revenue.
Adding Email Validation to Laravel: A Step-by-Step Guide
Learn how to integrate real-time email validation into your Laravel application using a custom validation rule, service class, and queue job for async processing.
Building a Fraud Prevention Middleware in Node.js
A step-by-step tutorial for building Express middleware that validates emails, checks IPs, and scores risk before requests reach your application logic.