60 BPM · beep every 1.0s
50%
Beep Offset: 0 ms
How to use:
Quick (by ear): Start the test, then drag the Beep Offset slider until the flash and the beep feel simultaneous. The slider value is your system's A/V offset — enter its opposite into your TV or receiver's Lip Sync / Audio Delay setting.
Precise (with camera):
1. Turn up your volume. Start the test.
2. Use your smartphone to record a video of this screen (use 60fps or Slow Motion mode for best results).
3. Playback the video frame-by-frame.
4. Find the exact frame where you hear the Beep. Check the position of the scanner line. If it's past the center (0ms) into the positive numbers, your audio is late.
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Download ShrinkFile for MacA/V Sync Tester
Calibrate your audio-visual equipment latency with frame-level precision.
Online Audio Video Sync Test
A professional-grade, frame-accurate tool to measure audio latency and video delay. Whether you are a video editor synchronizing sound in post-production, a gamer calibrating a home theater system, or a developer testing Bluetooth latency, this tool provides the physical reference point you need.
Reference Flash & Beep
Uses a high-contrast visual flash synchronized perfectly with a 1kHz sine wave beep. By recording this output with a high-speed camera (e.g., iPhone Slow Motion), you can count the frames between the visual event and the audio event to determine exact millisecond delay.
Check Bluetooth Latency
Wondering why your AirPods / Bluetooth headphones feel laggy? Run this test to visually see the delay. Typical Bluetooth latency is between 100ms - 300ms, which will show up clearly on our radar visualizer.
Home Theater Calibration
Use this pattern to adjust the "Audio Delay" or "Lip Sync" settings on your TV or AV Receiver. Adjust your equipment settings until the beep sounds exactly when the radar hits the 12 o'clock mark.
Variable Speed (BPM)
Adjust the loop speed from 30 to 120 BPM. Slower speeds help with initial coarse adjustment, while faster speeds (like 60 or 120 BPM) mimic standard video frame rates for fine-tuning.
OBS & Streaming Audio Sync
Having audio desync issues on Twitch or YouTube? Use this tool to capture a window in OBS, record the output, and calculate the exact "Sync Offset" or "Audio Delay" filter value needed for your microphone or capture card to achieve perfect stream sync.
Video Editing & Lip Sync
Whether you are using Premiere Pro, Final Cut Pro, or DaVinci Resolve, out-of-sync audio is a nightmare. Play this generator on your production monitor, record it through your camera's mic, and align the audio waveforms with the visual flash on your timeline.
Gaming Headset Latency Test
Test the real-world latency of your wireless gaming headset or TWS earbuds. Our frame-accurate radar helps you identify if your audio setup meets the sub-50ms threshold required for competitive FPS gaming.
Soundbar & eARC Delay Fix
Fix lip sync issues caused by HDMI eARC or optical audio processing delays. Run this test video on your smart TV or Apple TV browser and adjust the A/V Sync or Lip Sync Delay setting on your Soundbar or AV Receiver.
Microphone Auto-Measurement
No camera needed: click Auto-Measure with Mic and the tool listens for its own beeps through your microphone, then reports the median acoustic delay over 10 beats. Perfect for quickly comparing Bluetooth headphones, TWS earbuds, and wired setups.
Downloadable 60fps Test Video
Export a 10-second WebM test clip with embedded beeps and play it from a USB stick or media player on your TV — ideal for calibrating soundbars and AV receivers where a browser isn't available. Need MP4? Convert the clip with ShrinkFile below.