lan speed test

LAN speed test

Measure throughput between two browsers on the same local network using a direct WebRTC data channel.

How privacy works here
When a direct connection is established, test data travels between the paired browsers and never leaves your local network. inasec only handles short-lived connection setup data (a WebRTC offer, answer, and ICE candidates). Setup data expires within five minutes and is not logged. STUN is used for connection setup; TURN is disabled, so a relayed connection will not be reported as a LAN speed.

Open this page on the two devices you want to compare. On one device press Host test. On the other press Join test, then enter the pairing code or scan the QR shown by the host. Everything runs in your browser.

What this measures
The tool measures browser-to-browser throughput over a WebRTC data channel. That approximates the effective Wi-Fi or Ethernet bandwidth between the two devices at this moment. It is not the negotiated link speed of your router or Wi-Fi radio.
Why the connection type matters
A test that stays entirely on your local network shows a green Direct local classification. If the browsers can only reach each other by going through the public internet (hairpin NAT), the result is not a LAN test. If browsers cannot establish a direct connection at all (guest Wi-Fi with client isolation, some VLAN setups), the tool refuses to fall back to a relay.
Interpreting the number
Modern Wi-Fi 5 usually delivers 200 to 500 Mbps between two devices in the same room; Wi-Fi 6 can go higher. Wired gigabit Ethernet typically shows 800 Mbps or above browser-to-browser. Numbers well below that suggest either the wireless link, the device processor, or an intermediate switch is the bottleneck.
Want to compare this with your Internet connection?
Try the internet speed test

Frequently asked

What does a LAN speed test measure?
It measures throughput between two browsers on your local network using a direct WebRTC data channel. That gives an estimate of the effective Wi-Fi or Ethernet bandwidth between the two devices, not the negotiated link speed.
Does this test measure my internet speed?
No. The data flows directly between the two paired browsers on your local network. If you want to test your internet connection, use the internet speed test tool.
Do both devices need to be on the same Wi-Fi?
They need to be able to reach each other. That usually means the same Wi-Fi network. Networks that isolate clients from each other (some guest Wi-Fi, some enterprise Wi-Fi) will prevent a direct connection.
Does the test data leave my network?
When the connection is classified as Direct local, no test data leaves your LAN. Only short signaling messages (the initial connection negotiation) go through inasec. Those messages are held in Redis with a five-minute expiry and are never logged.
Why could the devices not connect?
The most common reasons are network isolation (guest Wi-Fi, mDNS blocked, different VLANs), aggressive firewall rules, or a browser that does not support WebRTC well enough for a direct link. The tool never falls back to a relay.
Is this the same as iperf?
It is a lightweight browser-only alternative. Real iperf measures raw TCP or UDP between dedicated processes. This tool measures WebRTC data channel throughput, which behaves close to a real user flow but is bounded by the browser SCTP implementation.