Morse Code Standard, Timing & Tool Testing
Last reviewed: August 26, 2026
This page identifies the primary International Morse code reference used by Morse Code Translates, explains the timing rules behind dots and dashes, and publishes repeatable checks for translator, decoder, audio, and practice tools.
Primary standard
The main reference is ITU-R Recommendation M.1677-1, International Morse code. The ITU lists this recommendation as in force and provides the official characters and operational provisions used in radiocommunication services.
The site uses the familiar written representation of a dot as . and a dash as -. Tool output should be treated as educational and general-purpose reference material. Operational, licensing, aviation, maritime, emergency, military, or regulated communication requirements should be confirmed with the responsible authority.
Signal timing
Morse rhythm is based on one time unit. A dot lasts one unit and a dash lasts three units. Signals within one character are separated by one unit, characters are separated by three units, and words are separated by seven units. Changing playback speed changes the duration of a unit while preserving these ratios.
Written Morse needs an unambiguous spacing convention. On this site, spaces separate characters and a slash may be used to make a word boundary visible. A decoder cannot reliably recover the intended message when every dot and dash is pasted without character or word boundaries.
Repeatable tool checks
| Area | Test input | Expected result |
|---|---|---|
| Letters | SOS |
... --- ..., with three dots for S and three dashes for O. |
| Numbers | 2026 |
..--- ----- ..--- -..... |
| Mixed text | TEST 5 |
Characters remain in order and the word boundary is visibly different from character spacing. |
| Decoder | .... . .-.. .-.. --- |
The decoded text is HELLO. |
| Unsupported input | An unsupported symbol | The interface identifies, ignores, or preserves the unsupported character consistently rather than silently inventing a Morse mapping. |
| Audio ratio | Play a character containing dots and dashes | A dash is three times the signal duration of a dot; spacing remains distinguishable at the selected speed. |
| Copy and download | Generate a short result | Copied text matches the visible output. Generated audio represents the same sequence shown on screen. |
| Mobile layout | Use the tool on a narrow screen | Input, output, playback controls, and primary actions remain usable without horizontal page scrolling. |
Language-specific pages
International Morse code does not provide a unique sequence for every character used by every writing system. A language page must therefore state whether it uses an established extension, transliteration, normalization, or a limited site-specific mapping. Accented letters and Arabic-script input should never be described as universally standardized when they are being normalized or transliterated for compatibility.
Visitors should review the explanation shown on the Spanish Morse page or Arabic Morse page before relying on the result.
Browser and audio limitations
Audio playback and file generation depend on browser audio support, device volume, autoplay rules, available memory, and power-saving behavior. Frequency and words-per-minute controls affect how a sequence sounds, but a web generator is not a calibrated radio transmitter. Background tabs and sleeping devices may delay playback events.
Report a correction
A useful report includes the page URL, exact input, visible output, expected output, browser, and device type. Do not include passwords or confidential messages. Send reproducible errors through the contact page. Learn more about maintenance and review on the About page, or test a sequence with the Morse translator, decoder, and audio player.