Characters with and without spaces, words, bytes and reading time. Set a limit and watch what is left.
Application forms usually count characters with spaces. Academic abstracts often say without spaces, and some government or Korean job portals count bytes. The instructions always say which one; this page shows all three so you can match it.
Korean and Japanese forms that say "2,000 bytes" almost always mean the legacy rule where a CJK character is 2 bytes and Latin letters are 1. Modern files are stored as UTF-8, where a CJK character is 3 bytes. Use the count that matches the form you are filling in.
Whether a line break counts, and whether an emoji built from several code points counts as one, changes the total by one or two. This page counts what a reader sees as one character (grapheme clusters) and treats line breaks as whitespace. Leave a margin of 5–10 characters under any hard limit.
Reading time assumes about 1,000 characters per minute of English, roughly 200 words. The page estimate uses 250 words per double-spaced page.
Nowhere. Counting happens in your browser, and the text is kept only in this browser's local storage so it survives a reload. Clear removes it.
About 80–100 English words. For Korean, 500 characters is roughly 100–125 words.
Word ignores line breaks and counts some punctuation differently. The form you are submitting to is the final judge, so check there once more.