What Is the Underscore in Morse Code?
The underscore (_) in Morse code is ..--.- — a 6-signal sequence: dot, dot, dash, dash, dot, dash. Often used in callsigns, file names, and email-style addresses sent over CW.
When you search for “underscore in morse code”, “morse code for underscore”, or “_ in morse code”, the answer is the same ITU-standard pattern: ..--.-. Other common names for this punctuation include underline, low line.
When to Use the Underscore
Use the underscore where written text would use it: in identifiers, usernames, file names, or as an underline marker. Common in modern digital-bridge CW such as packet radio addresses.
Practice: What Is the Morse Code for the Underscore?
Select the correct Morse code for the underscore (_):
How to Tap the Underscore in Morse Code
To transmit the underscore (..--.-), use this sequence:
ITU Timing Rules
- Dot (·) = 1 unit
- Dash (−) = 3 units (3× longer)
- Signal gap = 1 unit
- Letter gap = 3 units
- Word gap = 7 units
Timing Reference Table
| Speed | Dot | Dash | Letter gap | Word gap |
|---|---|---|---|---|
| 5 wpm | 240ms | 720ms | 720ms | 1680ms |
| 10 wpm | 120ms | 360ms | 360ms | 840ms |
| 17 wpm (this page) | 70ms | 210ms | 210ms | 490ms |
| 20 wpm | 60ms | 180ms | 180ms | 420ms |
How to Remember the Underscore in Morse Code
Two dots, two dashes, dot-dash — a low-then-high-then-low rhythm, just like a horizontal line beneath a row of letters.
Frequently Asked Questions — Underscore in Morse Code
The underscore (_) in Morse code is ..--.- (3 dots, 3 dashes). It’s the standard ITU code used worldwide.
The Morse code for the underscore is ..--.-. Tap the sequence as: dot, dot, dash, dash, dot, dash, with a one-unit gap between each signal.
To send the underscore: short tap, then short tap, then long press, then long press, then short tap, then long press. Keep one unit of silence between each signal and three units between this character and the next.
The underscore uses 6 signals total: 3 dots and 3 dashes.
Use the underscore where written text would use it: in identifiers, usernames, file names, or as an underline marker. Common in modern digital-bridge CW such as packet radio addresses.
Yes — ..--.- is defined by the ITU (International Telecommunication Union) Recommendation M.1677 and is used worldwide for the underscore.
Related Morse Code Punctuations
Other punctuations commonly used alongside the underscore: