You’ve probably looked at your keyboard a thousand times without really thinking about why the letters are where they are. It feels random. It’s not. Well, actually, the QWERTY layout was designed to slow you down so old typewriter arms wouldn't jam, but the actual frequency of English letters is the invisible hand behind almost every piece of communication technology we’ve ever built. From the way Samuel Morse assigned dots and dashes to the way Google predicts your next text message, some letters just work harder than others.
If you’re a Scrabble player, you know "E" is worth one measly point while "Z" is a goldmine. That's not just a game mechanic; it’s a reflection of how our language actually functions. In a standard 100,000-word English text, you’ll see the letter E roughly 12,000 times. You’ll see Z maybe 70 times. That is a massive, staggering gap.
The ETAOIN SHRDLU Mystery
Back in the day, when newspapers were set with hot lead on Linotype machines, operators noticed a pattern. The letters weren't just random; they fell into a specific order of popularity. They actually grouped the most common letters together to make their jobs faster. This gave birth to the famous (and slightly unpronounceable) string: ETAOIN SHRDLU.
If you ever see a weird jumble of letters like that in an old digitized newspaper archive, it’s not a ghost in the machine. It’s the typesetter’s equivalent of a "test page." They’d run their fingers down the first two columns of the keyboard to clear a line of type. Those twelve letters—e, t, a, o, i, n, s, h, r, d, l, u—make up about 80% of everything we write.
Think about that.
Twelve characters do almost all the heavy lifting. The other fourteen are just along for the ride, filling in the gaps when we need to talk about "pizzas" or "zebras."
Why E is Always the Protagonist
Why E? It’s the "schwa" sound. It’s the silent ending. It’s the workhorse of our vowels. In English, vowels are the glue, but E is the superglue. According to extensive analysis of the Oxford English Dictionary and the Brown Corpus—a massive collection of samples from various sources—E holds a steady lead at about 12.02% of all letter usage.
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T comes in second at 9.10%. Why? Because of "the," "that," "there," and "then." Our most common function words are built on the back of the letter T. If you’re trying to crack a simple substitution cipher—like those puzzles in the back of a Sunday magazine—always look for the most frequent symbol and guess it's an E. If there’s a three-letter word appearing constantly, it’s probably "the." Congratulations, you're now a cryptanalyst.
The Weird Physics of Morse Code
Samuel Morse wasn't just a tinkerer; he was a pragmatist. When he was designing the code that would eventually link the world via telegraph, he didn't just guess which letters should be short. He went to a local printing office.
He literally counted the number of type pieces in a printer’s case.
He saw that the "E" bin was overflowing with hundreds of pieces of lead, while the "X" and "Q" bins were almost empty. Because of this, he gave E the shortest possible signal: a single dot. He gave T a single dash. He gave the rare, "expensive" letters like Q and Z long, rambling sequences of dashes and dots.
This was essentially the first form of data compression. By making the frequency of English letters the basis of the code, he ensured that telegraph operators could send messages faster. If he’d accidentally swapped the code for E and Z, the entire history of the 19th-century communication would have been slower, clunkier, and much more prone to errors.
Digital Reality: How Your Phone Guesses Your Thoughts
Fast forward to 2026. Your smartphone’s predictive text and autocorrect are essentially high-speed statistical engines. They don't "know" what you’re saying. They just know that if you type "th," there is a statistically massive probability that the next letter is "e," "a," or "i."
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This is where letter frequency gets nuanced. There’s a difference between "general frequency" and "conditional frequency."
Basically, conditional frequency is the "what comes next" rule. While Q is one of the rarest letters in the alphabet, its conditional frequency for the letter U is nearly 100%. If you see a Q, you can bet your house a U is coming next. Software developers use these Markov chains—mathematical systems that transition from one state to another—to build the keyboards we use every day.
The Outliers: J, Q, X, and Z
On the other end of the spectrum, we have the "benchwarmers."
- Z: The least used letter, appearing about 0.07% of the time.
- Q: Just slightly more common at 0.10%, but almost entirely dependent on U.
- X: The scientific mystery letter, sitting at 0.15%.
- J: Often competing with Z for the bottom spot depending on the text source.
Interestingly, if you look at a dictionary instead of a conversational text, these numbers shift. In a dictionary, you have a lot more "P" and "C" words. But in real life, we don't talk like dictionaries. We talk in small, repetitive bursts of high-frequency words.
The "Benford’s Law" of Language?
In mathematics, Benford’s Law suggests that in many naturally occurring sets of numerical data, the leading digit is likely to be small (like 1 or 2). Language has a similar "power law" known as Zipf’s Law. It states that the most frequent word will occur twice as often as the second most frequent word, three times as often as the third, and so on.
While letter frequency doesn’t follow Zipf’s Law perfectly, the distribution is remarkably skewed. The top 9 letters (ETAOIN SHR) account for more than 70% of all usage. The bottom 8 letters account for less than 10%.
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This isn't just a fun fact for linguists. It's used in:
- Data Compression: ZIP files work by replacing frequent patterns (like "the" or "ing") with smaller codes.
- Genetics: Scientists use similar frequency analysis to map DNA sequences.
- Forensics: Determining if a document was written by a specific person based on their unique "letter fingerprint."
Practical Takeaways for Your Daily Life
You don't need to be a linguist to use this. Honestly, just knowing how letters behave can change how you interact with information.
For Wordle and Games:
Stop starting with "ADIEU." While it knocks out vowels, vowels are actually easier to guess once you have the consonants. Start with "STARE" or "CRANE." These use the highest-frequency consonants (S, T, R, N) alongside the king of vowels, E. You’ll narrow down the possibilities much faster.
For Password Security:
Don't just use common words. Because hackers know the frequency of English letters, their "brute force" programs are designed to try E, T, and A combinations first. If you want a truly strong password (that isn't just random gibberish), use "low-frequency" letters like Z, Q, and X in unexpected places. "Pizzax-Quilt" is weirdly harder for a basic frequency-based algorithm to guess than "Password123."
For Design and Coding:
If you're designing a user interface or a physical tool, put the most frequent "actions" where the most frequent "letters" would be. Keep the high-use items in the center of the field of vision. It's why the most used buttons on a game controller are the easiest for your thumbs to hit.
The way we speak and write isn't just a collection of sounds. It's a structured, predictable system of probabilities. Every time you type a text or read a billboard, you're seeing a massive statistical hierarchy in action. The letter E isn't just a vowel; it's the undisputed heavyweight champion of the English language.
To really see this in action, take a random page of a book and try to find a single sentence that doesn't use the letter E. It’s remarkably difficult. In fact, an author named Ernest Vincent Wright once wrote a 50,000-word novel called Gadsby without ever using the letter E. It’s an incredible feat of mental gymnastics, precisely because he was fighting against the natural, overwhelming gravity of English letter frequency.
Next time you’re stuck on a crossword or wondering why your "E" key is the first one to lose its paint, you’ll know why. It’s just the math of the way we talk.