Overview
Introduction
Word puzzles, "guess the missing letter" games, and fuzzy-search test data all benefit from words with a letter deliberately removed.
Doing that by hand for a whole passage is slow; this tool does it automatically.
What Is Random Letter Remover?
A tool that scans your text for words of 4 or more letters and removes one random letter from an interior position (never the first or last letter) of each one.
It runs entirely client-side as part of this site's String Tools collection, so nothing you paste is ever uploaded to a server.
How Random Letter Remover Works
For each alphabetic run of 4 or more letters, the tool picks a random index strictly between the first and last character and deletes that character, leaving shorter words and words under 4 letters untouched.
The randomness is seeded from your input text, so the same input always produces the same result rather than a new one on every run.
When To Use Random Letter Remover
Use it to build a "fill in the missing letter" word puzzle, or to generate imperfect input for testing a spell-checker or fuzzy search.
It's a fast way to get the answer without opening a code editor, a REPL, or writing a one-off script just to check.
Often used alongside Random Symbol Remover, Text Error Introducer and String Length Counter.
Features
Advantages
- Keeps the first and last letter intact, so the word stays recognizable as a puzzle prompt.
- Deterministic output for a given input, useful for reproducible puzzles or test fixtures.
- Seeds its generator from the input text itself, so the same passage always produces the same puzzle instead of changing on every reload.
Limitations
- Words under 4 letters are left completely unchanged.
- Only one letter is removed per word; there's no option to remove multiple letters from longer words.
Examples
Best Practices & Notes
Best Practices
- Use on longer words for the most legible puzzle results, since removing a letter from a 4-letter word can make it much harder to guess.
- Combine with the Random Symbol Remover for a more thorough obfuscation pass.
- Feed in the complete passage rather than one word at a time, since the seed derives from the whole text and any edit changes every result.
Developer Notes
Word matching uses the regex /[A-Za-z]{4,}/g, and the removed index is chosen with a mulberry32 PRNG seeded from a hash of the full input text (not Math.random()), so the transform is pure and reproducible across renders.
Random Letter Remover Use Cases
- Creating a "missing letter" word puzzle
- Generating imperfect input to test a spell-checker or fuzzy matcher
- Building a hangman-style word game prompt
Common Mistakes
- Expecting short words (under 4 letters) to be affected; they're always left as-is.
- Assuming re-running on the same text gives a different result each time; the removed letter is deterministic per input.
Tips
- Pair this with the Text Error Introducer tool if you want a mix of dropped, swapped, and duplicated letters instead of just drops.
- Words of three letters or fewer are left untouched, so short function words act as anchors that keep the sentence readable.