Lookup searches a versioned table of the HTML 4.01 named character references plus ' (253 names) by entity name (© or copy), by the character itself, by code point (U+00A9, ©, 0xA9) or by words in the description; the group filter narrows to Latin-1, symbols or special. Encode turns text into safe HTML using named references where one exists and numeric references otherwise; decode turns named and numeric references back into text. Source, version and review date are printed with every lookup. Everything runs locally.