Why are dots on the left and dashes on the right of the Morse code tree?

It is a convention, not part of the code. Every Morse character is a path of dots and dashes from the root, so any drawing of the Morse code tree has to send one branch each way. Drawing dots left and dashes right means reading a letter's code and following its path are the same left-to-right motion.

Why are some places on the bottom row of the Morse code tree empty?

The Morse code tree of the English alphabet is four rows deep, so its last row has room for 16 patterns of four elements, but only 12 of them are English letters. The other four stay empty rather than being filled with something made up, although other languages use some of them for letters such as Ä, Ö and Ü.

The Morse code tree

The Morse code tree shows why every character has the code it has. From the root, a dot branches one way and a dash the other, so each character sits exactly where its own code leads. E and T are one step from the root, the 4 two-element letters two steps away, and the 12 four-element letters four.

Signal tree · A–Z

Not met
Met
Learning
Mastered

Network power

0 of 26 mastered

How to read the Morse code tree

Start at the root, the ring at the top of the board. Every dot you hear is one step down and to the left, and every dash is one step down and to the right. Wherever you are standing when the character ends is the letter. So A, dot dash (·−), is one step left and then one step right.

How deep a letter sits is how long its code is. E and T are one step down because each is a single element. The second row holds four letters of two elements, the third row eight of three, and the fourth twelve of four. The 26 letters fill 4 rows, and the last row has room for 16 but uses only 12, which is why it has gaps.

Two letters side by side under the same parent differ only in their last element. That is why A (·−) and I (··), or D (−··) and K (−·−), are easy to mix up at first: they share everything but the ending. Pick any pad on the board to hear it at your own speed and tone, see its path from the root, and drill it on the spot, either by keying it or by naming it by ear.

Why it is also the best order to learn in

Learning the tree from the top down means the shortest characters come first, and each new row only adds one element to patterns you already know. You never meet a four-element letter before you can tell a dot from a dash.

That is the order the guided lessons and the 7-day plan follow. Day 1 is the top row, E and T. Each following day takes the next row, and a row too wide for one sitting is split across days. After six days you have all 26 letters, and the last day adds the ten digits: about 2 hours 15 minutes of practice in total.

Each pad shows how far along you are with that letter. A dashed pad is one you have not met. A thin ring means you have met it, an amber ring means you are learning it, and a lit pad means it is mastered. Mastered is a high bar on purpose: at least 10 answers in each of the three skills, reading the code, hearing it and sending it, and an average of 90% or better across them. The network power gauge under the board averages that progress over the whole alphabet, so it moves every time you practise. For the full list of codes, letters, digits and punctuation, see the Morse code alphabet.

Common questions

Why are dots on the left and dashes on the right of the Morse code tree?: It is a convention, not part of the code. Every Morse character is a path of dots and dashes from the root, so any drawing of the Morse code tree has to send one branch each way. Drawing dots left and dashes right means reading a letter's code and following its path are the same left-to-right motion.
Why are some places on the bottom row of the Morse code tree empty?: The Morse code tree of the English alphabet is four rows deep, so its last row has room for 16 patterns of four elements, but only 12 of them are English letters. The other four stay empty rather than being filled with something made up, although other languages use some of them for letters such as Ä, Ö and Ü.