Morse Code Translator
Convert text to Morse code and back with audio playback. Learn Morse code online with visual dots and dashes. Free Morse code translator
Morse code is older than the internet by 130 years and is still in use today — by amateur radio operators worldwide, by pilots reading VOR/NDB beacon identifiers, and as a backup encoding when other channels fail. The interesting thing about Morse is that it is a variable-length prefix code — common letters (E, T) are short, rare ones (Q, J) are long. This is the same idea Huffman coding formalized 100 years later. This translator converts text to Morse and back, plays audio at adjustable WPM, and supports International (the standard) and American (historical) variants.
How the code is structured
- Dot (.) — one unit. Pronounced "dit".
- Dash (−) — three units. Pronounced "dah".
- Inter-element space — one unit (between dot/dash within one letter).
- Inter-letter space — three units.
- Inter-word space — seven units.
- Common letters are short. E = · T = − A = ·− N = −· I = ·· M = −− S = ··· O = −−−
- Rare letters are long. Q = −−·− J = ·−−− Y = −·−− Z = −−··
The length distribution is roughly inverse-proportional to letter frequency in English — Samuel Morse and Alfred Vail counted type slugs at a print shop to estimate frequencies. The resulting code is within 15% of the optimal Huffman code for English; not bad for 1838.
Working example
Input
Text: HELLO WORLD
Output
H E L L O W O R L D ···· · ·-·· ·-·· --- ·-- --- ·-· ·-·· -·· At 20 WPM (1.2 seconds per word for "PARIS" standard): Total transmission time: ~6 seconds Famous codes: SOS = ··· −−− ··· (distress signal; 1908 international standard) ? = ··−−·· (most common error / "say again") AR = ·−·−· (end of message) SK = ···−·− (end of contact)
SOS is intentionally NOT three letters — it is one continuous nine-element sequence with no inter-letter spaces. The choice was pragmatic: easy to remember, unmistakable, fast to send. The "save our souls" expansion came later as backronym; the code was chosen for its rhythm, not its meaning.
WPM and the PARIS standard
WPM (words per minute) in Morse is measured by sending "PARIS" repeatedly — the word PARIS plus the inter-word space takes exactly 50 units. 1 WPM = 50 units per minute = 1 unit per 1.2 seconds. At 20 WPM, a unit is 60 ms; at 40 WPM, 30 ms. Operator proficiency:
- 5 WPM — first Morse code license tests (where still required). Letter-by-letter perception.
- 12-15 WPM — comfortable conversation pace for amateur radio.
- 20-25 WPM — typical experienced amateur radio operator.
- 35-50 WPM — competition-class operators. Hear words, not letters.
- 60+ WPM — exceptional. World-record territory.
When Morse is still used
- Amateur radio (ham radio) — popular mode (CW = continuous wave) because it punches through static when voice cannot. Most modern radios still have a Morse key jack.
- Aviation — VOR and NDB beacons identify themselves in Morse, three letters at 1020 Hz. Pilots cross-check the audio identifier against the chart before navigating by the beacon.
- Military — encrypted Morse over HF remains a backup when satellites and digital modes are jammed.
- Maritime — formally retired internationally in 1999 (replaced by GMDSS), but some operators still use it for ship-to-shore.
- Accessibility — single-switch Morse input is used by some people with severe motor disabilities. Two switches (dot and dash) is enough for full text entry.
When to reach for this tool
- You are learning Morse for an amateur radio license and want a reference + audio playback at your training pace.
- You are decoding a beacon identifier from a recording (aviation, ham radio) and want to spell it out letter by letter.
- You are setting up an Easter egg in an embedded device that blinks a hidden message in Morse via an LED.
- You are curious about how an old telegram or letter's coded reference would have read — convert and play back.
What this tool will not do
- It will not decode audio Morse from a microphone or file. Audio decoding requires DSP — pitch detection, noise filtering, timing extraction. Dedicated apps (fldigi, CW Decoder) handle this; this tool is text-to-Morse and text-from-Morse only.
- It will not handle non-Latin Morse variants without explicit support. Cyrillic, Greek, Arabic, Japanese (Wabun code) Morse variants exist; the translator supports International Morse (Latin) by default with American historical Morse as an option.
- It will not generate FCC-license-grade audio. The audio is a sine wave at adjustable frequency and speed — fine for learning. Real CW transmission requires a radio.
Frequently asked questions
Is Morse code still legally required for ham radio licenses?
No, not since the early 2000s in most countries (US dropped the Morse requirement in 2007; UK in 2003). It is still tested for some specialized licenses and remains the dominant mode in many parts of amateur radio.
Why is "E" just a single dot?
E is the most common letter in English (~12.7% frequency). Assigning it the shortest possible code minimizes the average message length. The code-length-to-frequency mapping was optimized empirically by Morse and Vail by counting type slugs at a print shop.
What is the difference between International and American Morse?
American Morse (Vail, 1840s) was the original, used on US landline telegraphs. International Morse (1865) standardized the codes for radio. The two differ on several letters (O is "· ·" in American, "− − −" in International) and punctuation. American Morse is essentially extinct; International is the standard.
How do you "type" Morse?
Traditionally with a straight key (one switch you tap). Modern operators use paddles — two levers, one for dots, one for dashes, with electronic keyers that maintain timing. Or computers (a keyboard plus software that converts each keystroke to its Morse code).
Can I send Morse with a flashlight?
Yes. Flashing Morse is the "code without the wire" form. Used historically by ships before radio. Useful as a survival skill — a flashlight or even a mirror flash can send SOS over miles. Practice: SOS is three short flashes, three long, three short.
Is Morse code Morse Sr. or Morse Jr.'s invention?
Samuel F. B. Morse (the painter and inventor) developed the telegraph; Alfred Vail (his collaborator) did most of the work on the code itself. The code is usually credited to "Morse" but Vail's contribution to the encoding was substantial. The historical convention is "Morse code" regardless.
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