Research and guides

Field notes, practical playbooks and integration guides. For the people protecting the next signup, login and checkout.

Latest

Detection research

Residential proxies on the White House network, and how to spot them

Proxy traffic left through the White House network 236 times in 30 days: how one device turns a network into a proxy exit, and how to spot the traffic.

Kaspar Tomson11 min
Fundamentals

Is my phone being used as a proxy? How to check, and how to stop it

How to tell whether your phone uses a proxy, or is quietly rented out as one by an app or a cheap TV box, the signs investigators list, and how to stop it.

Kaspar Tomson11 min
Fundamentals

“Unusual traffic from your computer network”: why websites think you’re a bot, and how to fix it

What Google’s “unusual traffic” page and endless CAPTCHAs mean: shared addresses, VPNs, apps and extensions that use your connection, and the fixes that work.

Kaspar Tomson10 min
Comparisons

MaxMind vs IPinfo vs IP2Location: IP geolocation APIs and databases compared

MaxMind, IPinfo, IP2Location, DB-IP, ipgeolocation.io and ip-api compared from their own pages: free databases and APIs, licences, updates, prices and accuracy.

Kaspar Tomson9 min
Fundamentals

What is an ASN? Autonomous system numbers explained, and how to find the ASN of an IP

An ASN identifies a network that routes its own IP addresses. What autonomous system numbers are, who gets one, reserved ranges, and how to find an IP’s ASN.

Kaspar Tomson7 min
Fundamentals

Can websites tell you’re using a VPN? How they know, and why yours gets flagged

Usually, yes. How websites tell you’re on a VPN, why some block it or ask for more, why “VPN detected” appears without one, and how to check yours.

Kaspar Tomson9 min
Comparisons

Proxy detection APIs compared: free tiers, residential and mobile proxies

Thirteen proxy detection APIs compared from their own pages: which free plans flag residential proxies, which charge for it (from $19 a month) and the terms.

Kaspar Tomson15 min
Fraud playbooks

Email bombing: what to do when your inbox is flooded, and how to keep your forms out of it

Inbox flooded with signup emails? What email bombing and list bombing are, what to do in Gmail or Outlook, whether it is illegal, how sites stop it.

Kaspar Tomson17 min
Integration guides

Datacenter IP detection: how it works and what it cannot tell you

How datacenter IP detection works (cloud range files, the routing table, live visits) and why a cloud address alone is not evidence of fraud.

Kaspar Tomson12 min

Most read

Last 90 days
  1. 01How to Detect Residential Proxies in 2026Fraud playbooks15 min
  2. 02Free VPN Detection APIs Compared: Limits, Inputs and TermsComparisons11 min
  3. 03Card Testing Attacks: How Bots Drain Stripe Accounts in 2026Fraud playbooks11 min
  4. 04Headless Browser Detection in 2026: What Still WorksDetection research7 min
  5. 05CAPTCHA Farm Economics: How $0.001 per Solve Killed Bot DetectionDetection research10 min
  6. 06Detecting Antidetect Browsers in 2026Detection research15 min
  7. 07How to Detect Puppeteer & Playwright in 2026Detection research6 min
  8. 08Shopify Bot Detection: Checking Drop Orders Before They ShipIntegration guides8 min

Detection research

What we see when we put a tool on the bench.

All 18 articles

Fraud playbooks

One attack per post: how it is run, why the usual control misses it, and where the check goes.

All 21 articles

Integration guides

Working code for the framework you use.

All 25 articles

Comparisons

Head-to-heads and category round-ups, including the cases where the other vendor is the right answer.

All 9 articles

Fundamentals

The definitions the rest of the site assumes you have.

All 9 articles

About these images

Fraud BriefOnce a month · no spam

The VPN, proxy and bot patterns we saw this month

One email a month with what changed in the traffic we check — new VPN and proxy networks, new bot tooling, what our lab runs turned up. Written for engineers. Unsubscribe in one click.