Alphanumeric Only in JS
Match strings containing only letters (A–Z, a–z) and digits (0–9), with no spaces or special characters.
Try it in the JS tester →Pattern
regexJS
^[a-zA-Z0-9]+$JavaScript / ECMAScript code
jsJavaScript
const re = new RegExp("^[a-zA-Z0-9]+$", "");
const input = "Hello123";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).
How the pattern works
^ and $ anchor to the full string. [a-zA-Z0-9]+ requires one or more characters from the combined letter and digit set. Any space, punctuation, or symbol will cause the match to fail.
Examples
Input
Hello123Matches
Hello123
Input
abcMatches
abc
Input
has spaceNo match
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