How to Decode Morse Code From an Audio Recording (Step-by-Step, Free)

Quick answer

Open the free Morse Code Audio Translator, drop in your recording (WAV, MP3, M4A, OGG or WebM, up to 5 MB), leave Detection Sensitivity on Auto, and click Analyze Audio. The tool shows the detected dots and dashes and the decoded text side by side. If the sound is playing live — from a speaker, a radio or another device — use the Live Morse Audio Translator and let it listen through your microphone instead.

If the result looks like nonsense, don't give up: jump to 7 reasons the output is gibberish. Most problems come from noise, speed, or a recording that is not clean enough, and most of them are fixable.

How an audio decoder "hears" Morse code

Morse code in audio is just a tone switching on and off. A decoder doesn't understand letters directly — it measures how long each beep and each silence lasts, then maps those lengths to dots, dashes and gaps.

International Morse code uses a fixed timing ratio based on one unit:

The speed of Morse is described in words per minute (WPM). Using the standard word "PARIS" (50 units long), one unit in milliseconds is roughly 1200 ÷ WPM. At 20 WPM a dot lasts about 60 ms; at 10 WPM it lasts about 120 ms.

So the decoder's job is: find the tone, measure the pulses, estimate the unit length, then classify each pulse as a dot or dash and each silence as a letter or word gap. MorseClue's audio translator estimates the dot unit from the pulse lengths in your file before translating — that's why a steady, consistent recording decodes much better than a shaky one. If you want to check letters by hand, keep the Morse code chart open.

Step-by-step: decode a Morse recording with MorseClue

1. Prepare the file

• Supported formats: WAV, MP3, M4A, OGG, WebM; maximum size 5 MB.
• Trim long intros, speech or music around the Morse. The cleaner the clip, the better the result.
• If your file is larger than 5 MB, cut it down to just the Morse part or export a shorter segment.

2. Upload and analyze

1. Go to https://morseclue.com/en/tools/audio-decoder.
2. Choose or drag your file onto the upload area.
3. Keep Detection Sensitivity on Auto for the first try.
4. Click Analyze Audio.

3. Check the result

You'll see two outputs: Detected Morse (the dots and dashes) and Decoded Text. Compare them: if the dots and dashes look right but some letters are odd, it's usually a spacing problem. If the dots and dashes themselves look random, the tone wasn't detected cleanly.

4. Fine-tune if needed

• Detection Sensitivity: if quiet beeps are missed, raise it; if background noise turns into extra dots, lower it.
• Minimum Pulse (default 20 ms): increase it to ignore clicks, pops and very short noise bursts. Don't set it above the length of a real dot (see the 1200 ÷ WPM rule above).
• Click Analyze Audio again after each change, then Download Result to save the text.

Live audio: decode through the microphone

For sound you can play but can't easily save as a file, open the Live Morse Audio Translator and click Start Listening. Set Expected Speed (WPM) close to the source — the tool shows the matching unit length in milliseconds — and adjust Sensitivity until background noise stays below the detection line. Use a quiet room and keep the speaker close to the microphone.

Decoding Morse code in TikTok, YouTube and other videos

Morse code shows up a lot in videos: puzzle channels, game trailers, ARGs, music tracks with hidden messages. You have two options:

1. Play it into the microphone. Open the live audio tool, start listening, and play the video on another device (or the same device's speaker). This is the fastest way, but room noise and speaker quality will affect accuracy. Replay the clip a few times if needed.
2. Extract the audio first. If you have the video file itself (for example, one you recorded or exported), save its sound as an audio file — many video editors and converters can export M4A, MP3 or WAV — trim it to the Morse section, and upload it to the audio translator. Only download content you have the right to use.

Tip: background music and voice-over are the biggest problems in video Morse. If the beeps sit under music, the decoder may only catch part of the message.

And if the Morse in the video is visual — flashing lights or dots and dashes on screen — take a screenshot and try the image translator instead.

7 reasons the output is gibberish (and how to fix them)

1. Background noise. Hiss, hum, voices or wind create false pulses. Fix: trim to the cleanest section, lower sensitivity, and raise Minimum Pulse to filter short noise.
2. Echo or reverb. A recording made in a room (or a speaker recorded by a phone) smears each beep, so gaps get "filled in" and letters merge. Fix: record closer to the source, in a smaller or softer room, or use the original file instead of re-recording it.
3. More than one tone. Two signals at once, or Morse mixed with music, confuses the detector. Fix: cut the clip to where only one tone is audible.
4. Speed drift. Hand-sent Morse (straight key or "fist") often speeds up and slows down. Since the decoder estimates a single unit length, big changes in speed cause dots and dashes to be confused. Fix: decode shorter sections separately.
5. Farnsworth spacing. Learning material often sends letters fast but adds extra space between letters and words. Long gaps can be read as word breaks, adding extra spaces. Fix: read the Detected Morse line and fix spaces manually, or decode the letters with the chart.
6. Heavy compression. Low-bitrate MP3s or audio that has passed through a phone call or social app can lose the sharp start and end of each beep. Fix: use the highest-quality version you can find; WAV is ideal.
7. Clip too short or too long. A few beeps don't give enough data to estimate the timing; a long recording with changing conditions mixes several situations together. Fix: aim for a clip that contains a full message with several letters, but trim away anything that isn't Morse.

If none of this helps, try the live tool with the Expected Speed set manually — giving the decoder the right WPM can make a big difference.

What about ham radio (CW) recordings?

Clean CW recordings with a strong signal often decode well in a browser tool. Real on-air recordings are harder: weak signals, fading, interference and several stations close together are common. For serious ham radio work, dedicated CW decoding software built for radio receivers (for example CW Skimmer or Morse Expert, among others) is usually the better choice, because it is designed to filter and track signals in noisy bands. MorseClue is best for quick, free decoding of reasonably clear recordings.

And honestly, the most reliable decoder is your own ear — if you want to get there, practise with the Morse trainer.

Privacy: your audio stays on your device

MorseClue's audio and live translators run locally in your browser. Your recording is analyzed on your own device and is not uploaded to a server, and the microphone stays off until you click Start Listening. That makes it safe to decode personal voice memos, private puzzle files or anything you'd rather not share.

Make your own test audio (WAV)

Not sure whether the problem is your recording or your settings? Create a clean reference file:

1. Open the MorseClue translator on the home page.
2. Type a short message, e.g. SOS TEST 123.
3. Play it to check, then download it as a WAV file.
4. Upload that WAV to the audio translator.

A generated file should decode cleanly. If it does but your recording doesn't, the issue is the recording quality — go back to the seven fixes above. You can also play the test file from a speaker into the live tool to see how much your room and microphone affect the result.

FAQ

Can I decode Morse code from an audio file for free?

Yes. MorseClue's audio translator is free, needs no sign-up, and runs in your browser. It accepts WAV, MP3, M4A, OGG and WebM files up to 5 MB.

Is my audio uploaded anywhere?

No. Decoding happens locally in your browser, so the file stays on your device.

Why does my decoded text have wrong letters or random spaces?

Usually it's noise, echo, changing speed or extra spacing (Farnsworth timing). Trim the clip, adjust sensitivity and minimum pulse, or decode shorter sections.

How fast can the Morse code be?

Speed matters less than clarity. Clean, consistent beeps decode best; at higher speeds the dots get very short (about 1200 ÷ WPM milliseconds), so noise and compression have a bigger effect.

Can I decode Morse code from a video?

Yes. Play the video into the live microphone translator, or export the video's audio and upload it to the audio translator.