Two-Phone Sound Radar
Open it on two phones a known distance apart; clap or talk and a live dial swings toward the sound — two ordinary phones become a directional microphone array.
- 📱 Device Tool
- ✓ Free
- ✓ No sign-up
- ✓ Private — runs in your browser
- ✓ Any device
Pair two phones, clap once, and watch the radar point toward the sound.
This device can't run Sound Radar
Open this on your second phone
Scan the code, or type the short code into Sound Radar on the other device.
Join the other phone
Type the short code shown on the host phone (or open its link).
Pair both phones on the same Wi-Fi (peer-to-peer, nothing is uploaded).
Lay them flat a known distance apart and tell us that baseline gap.
We sync their clocks, both phones listen, and a sharp clap reveals the direction.
Pick which side this phone sits on. Both phones must agree — set the other one to the opposite side.
Wider gap = more accurate angle. Beyond the baseline, sound from far away arrives almost in parallel.
Sync is shaky (high jitter). Keep both phones awake on the same Wi-Fi and re-sync for a sharper reading.
We ping-pong timestamps NTP-style to line up this phone's clock with the host's. Tap this on both phones — each one syncs itself. Re-run if either phone was just unlocked.
Both phones will ask for microphone permission.
Higher = reacts to softer sounds (and more false triggers). Lower = needs a sharp, loud clap.
🧪 Fun approximation. Phone mics, Wi-Fi clock sync and audio buffering each add a few milliseconds of jitter — and sound travels ~343 m/s, so a 0.3 m gap is under a millisecond of difference. Treat the needle as a playful estimate, not a survey instrument. 100% on-device & peer-to-peer — no audio ever leaves your phones.
Why you’ll love Two-Phone Sound Radar
How to use it
- 01
Open it
No download and no login — the tool is ready right at the top of this page.
- 02
Use it
Enter your details or start interacting. Everything updates live as you go.
- 03
Get your result
Copy, download or share your result in a single tap. That’s it.
About Two-Phone Sound Radar
Turn two ordinary phones into a directional microphone array with this browser-based sound radar. Position two phones a known distance apart, then clap or talk—a live dial swings toward the source, letting you pinpoint sound direction in real time. It's an elegant demonstration of acoustic localization using your existing devices.
The tool runs entirely in your browser with no signup required, and your audio data never leaves your device. By comparing sound arrival times between two phones, it calculates the direction of incoming sound, functioning as a two-phone radar for sound triangulation. Open it instantly on any mobile device and start locating sound sources without any special equipment or configuration.
Perfect for understanding how directional microphones work or spotting where a sound is coming from in your environment. Since both phones stay local to your network, everything happens privately on your devices. Refresh your understanding of acoustic principles with a genuinely useful tool that proves two phones can become much more than phones.
Popular uses
- ✦ Locate the direction of a bird call or animal sound outdoors
- ✦ Find where a beeping device (phone, alarm, pet tracker) is hiding in your home
- ✦ Demonstrate acoustic localization principles to students or teach how directional audio works
- ✦ Test speaker positioning and sound distribution in a room or small venue
- ✦ Help identify which direction background noise or audio feedback is coming from
Frequently asked questions
How accurate is the sound direction finder?
Do I need to install anything or create an account?
What's the difference between this and a real microphone array?
Is my audio data safe and private?
Is Two-Phone Sound Radar free to use?
Is my camera or mic data uploaded?
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