VPN & Proxy Detection — JapanDetect VPN, Proxy & Bot Traffic from Japan
Sentinel scores every visitor's network in real time — flagging VPN exit nodes, residential proxies, datacenter ASNs, and headless browsers originating from Japan. Free API. Under 40ms. No CAPTCHAs.
Why Japan traffic needs special scrutiny
Datacenter ASN concentration
Japan is NTT and SoftBank residential ranges are the most common origin for Asia-targeted SaaS fraud.
Residential proxy resale
Consumer ISP ranges in Japan are routinely sold through residential proxy networks like ShadowNode and Bright Data. These IPs look real but rotate every few minutes — a clear bot signature once you know what to look for.
VPN exit-node clustering
The same handful of hosting providers dominate VPN exit nodes in Japan. Sentinel maintains live mappings of these ranges so a new IP from a known VPN ASN is flagged within seconds of going live.
Antidetect browser usage
Multi-accounting fraud against Japanese-targeted SaaS, fintech, and e-commerce increasingly uses Kameleo, GoLogin, or AdsPower to spoof device fingerprints. Sentinel scores these at the device layer, not the IP layer.
What Sentinel detects for Japan traffic
- Every major VPN provider's Japanese exit nodes (NordVPN, ExpressVPN, ProtonVPN, Mullvad, Surfshark, and 40+ more)
- Residential proxy networks reselling consumer Japanese IPs (ShadowNode, Bright Data, Smartproxy, Oxylabs)
- Datacenter ASNs commonly used for automation (AWS, GCP, Azure, OVH, Hetzner, DigitalOcean, Vultr, Linode)
- Tor exit nodes and known anonymous relays advertising Japanese geolocations
- Headless browsers (Puppeteer, Playwright, Selenium) and antidetect tooling driving sessions from Japan
- Country-spoofing — when a session claims to be in Japan but the network telemetry says otherwise
One API call. Bearer token. Done.
const r = await fetch('https://sntlhq.com/v1/evaluate', {
method: 'POST',
headers: { 'Authorization': 'Bearer sk_live_...' },
body: JSON.stringify({ token: sentinelToken })
});
const { decision, country, network } = await r.json();
if (country === 'JP' && network.vpn) blockOrChallenge();
Stop Japanese VPN, proxy & bot fraud today
Free tier. 1,000 API requests per hour. No credit card. Detects VPN, residential proxy, datacenter, and bot traffic from Japan and 195 other countries.