Morse Lux- One signal at a time. Music, speech or two Morse signals at once confuse every decoder.
- Not too loud, not too quiet. If the bar never drops back down, there is too much noise; if it barely moves, go closer.
- Give it a few letters. The decoder learns the speed from the first characters and gets more accurate after that.
- Practice your ear. A decoder is a great help, but nothing beats understanding Morse yourself — try the free Morse code trainer.
Morse Lux › Decoder
·–·· ··– –··– Free tool · microphone & audio files
Morse Code Decoder (Audio)
Hold your phone or laptop close to a Morse signal — a video, a radio, a recording — and watch it turn into text. Or open an audio file. The decoder finds the tone and the speed by itself.
Ready. Start the microphone, open an audio file or try the example.
🔒 Everything runs in your browser. The sound is not recorded, saved or uploaded.
How to decode Morse code from sound
- Start the microphone and allow access when your browser asks.
- Hold your device close to the loudspeaker, radio or the person sending. Keep background noise low.
- Watch the signal bar. Every beep shows up as a line, and the text appears live. The decoder finds the tone (300–1300 Hz) and the speed automatically.
- Or open a file — a recording, a voice memo or a video with Morse code.
Tips for better results
Want to create Morse audio?
Use the Morse code translator to turn text into Morse sound, play it at any speed and download it as a WAV file — then test it here.
Frequently asked questions
How does the Morse code decoder work?
It listens for a steady tone, measures how long each beep and each pause lasts and learns the speed from the difference between short (dots) and long (dashes) beeps. Pauses tell it where a letter or a word ends. The first letter can be wrong while it is still learning the speed — it corrects itself as more signal comes in.
Which sounds can it decode?
Morse code sent as a clear tone: recordings, YouTube videos, radio (CW), apps, a buzzer or a whistle. It works best with one tone at a time and little background noise. Speech, music or several signals at once make it harder.
Which speeds work?
From very slow (about 5 words per minute) up to about 40 WPM, including Farnsworth timing with extra-long pauses. Very irregular hand-sent Morse can produce wrong letters.
Can I decode an audio file?
Yes. Press “Open audio file” and choose an MP3, WAV, M4A, AAC, OGG or FLAC file — or a video file. It is decoded right in your browser, usually in a few seconds.
Is my audio uploaded or recorded?
No. Everything happens on your device. The sound from the microphone is analyzed live and immediately discarded; files are never uploaded.
Why does it show # or wrong letters?
A # means a pattern that is not a Morse character. Common reasons: background noise, echo, two signals at once or very uneven timing. Move closer to the sound, turn the volume up a little and make the room quieter.
Does it work on the iPhone?
Yes, in Safari and Chrome. For decoding on the go — also flashing lights with the camera — the Morse Lux app is made for it.