WiFi Signal Strength Checker

Your phone or router shows signal strength in dBm. Slide to your reading to see what it means. Closer to zero is stronger.

-55 dBm
WiFi signal strength chart
ReadingQuality
-30 to -50 dBmExcellent
-51 to -60 dBmVery good
-61 to -70 dBmGood
-71 to -80 dBmWeak
Below -80 dBmPoor
-55 Very good

What the numbers mean

WiFi signal is measured in dBm (decibel-milliwatts). The numbers are negative, and every 3 dB is roughly a doubling or halving of power. So −60 dBm is about four times stronger than −66 dBm, even though the numbers look close.

For the full explanation, including signal-to-noise ratio, read what is a good WiFi signal strength.

How to find your WiFi signal strength in dBm

Websites can’t read your WiFi signal (browsers block it for privacy), so check it on your device and enter it above:

How to improve a weak signal

Once your signal looks good, confirm the real-world result with the WiFi speed test.

Signal strength FAQ

Is −67 dBm a good WiFi signal?
Yes. −67 dBm is a commonly used minimum for reliable video calls and streaming, so it counts as good, though not as strong as −50 to −60 dBm.
Is −40 dBm better than −70 dBm?
Yes, much better. The closer to zero, the stronger the signal. −40 dBm is excellent; −70 dBm is borderline.
Why is my signal strong but my internet slow?
Signal is only the link between your device and router. Slow internet can come from a crowded channel, your plan, other devices, or your provider. Run the speed test and read why is my WiFi slow.

Guides for this tool

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