Morse Code Audio Decoder

Turn Morse code sound into text. Listen live through your microphone or upload a recording. The tone and speed are found automatically, and all decoding happens in your browser.

Start microphone Upload audio file Try example

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International Morse Code · Runs in your browser · Audio is not uploaded. Want to make Morse audio? Use the Morse code translator to play or download a WAV.

How to decode Morse code audio

  1. Press Start microphone and allow access, or press Upload audio file and choose a WAV, MP3, or OGG recording.
  2. Play the Morse. The signal bar moves with the tone and the square lights up while a dot or dash is heard.
  3. Read the text and the dots and dashes as they appear. The tone (Hz) and speed (WPM) found are shown above the settings.
  4. If letters look wrong, turn off Auto tone or Auto speed and enter the values you know. An uploaded file is decoded again right away.
  5. Press Copy text or Copy Morse to keep the result.

Tips for a clean decode

  • Use one steady tone. Two signals at once, music, or speech confuse the decoder.
  • Keep the microphone close to the speaker and the room quiet. Turn the volume up until the bar passes the threshold line on each dot.
  • Headphones on the same device will not work with the microphone. Play the sound through a speaker, or upload the file.
  • Give it a few letters. The speed is learned from the first dots and dashes, so the opening letters can be off.
  • A single repeated letter like T T T or E E E has no dots and dashes to compare. Set the speed by hand for those.
  • Uploaded files decode best. The whole recording is read at once, so speed changes are handled better than live.

How the decoder works

The decoder scans the 200 to 1600 Hz band for the strongest steady tone, then follows how loud that tone is every few milliseconds. A threshold that adapts to the background noise decides when the key is down. Mark and gap lengths are compared with the dot length: a dash is about three dots, a letter gap about three dots, and a word gap about seven. See how to learn Morse code for the full timing rules and the Morse code alphabet for every letter.

Frequently asked questions

How do I decode Morse code from audio?

Press Start microphone and allow access, then play the Morse near your device. Or press Upload audio file and pick a WAV, MP3, or OGG recording. The decoder finds the tone, measures the speed, and writes the dots, dashes, and text as it reads them.

Is my audio uploaded anywhere?

No. Decoding runs in your browser with the Web Audio API. Microphone sound and uploaded files stay on your device. Nothing is sent to our server or stored.

Which audio files work?

Any file your browser can play: WAV, MP3, and OGG work in all modern browsers, and M4A or WebM work in most. Files can be up to 25 MB and 15 minutes long. WAV files saved from our Morse code translator decode cleanly.

What speeds and tones can it read?

It reads about 5 to 50 words per minute and tones between 200 and 1600 Hz, which covers most practice files and amateur radio CW. It follows speed changes and Farnsworth spacing, where letters are fast but the gaps are longer.

Why are some letters wrong?

Noise, echo, a second tone, or uneven hand-sent timing can turn a dash into a dot or join two letters. Move closer to the speaker, lower background noise, and set the tone or speed by hand if you know it. The first letters can be misread while the decoder learns the speed.

Why does the microphone not start?

The browser may have blocked microphone access for this site. Allow it from the lock or site settings icon in the address bar and try again. If no microphone is connected or another app is using it, upload a recording instead.

Can it decode flashing lights or a picture?

No, this page only reads sound. For Morse drawn in an image, use the Morse code image translator. To type text or dots and dashes, use the Morse code translator on the home page.

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