Firefox
/ˈfaɪəfɒks/
"firefox" is a 7-letter English headword indexed on PlainSpell.
The verdict
“Firefox” is a moderately-common English word, ranked #16,915 in English word frequency and used as a proper noun.
- #16,915
- frequency rank, English
- 7
- letters
- 10
- tracked misspellings
- 1
- confusable pair
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A free, open-source, cross-platform, graphical web browser, developed by the Mozilla Foundation.
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | Firefox |
| Language | English |
| Part of speech | Proper noun |
| IPA | /ˈfaɪəfɒks/ |
| Letters | 7 |
| Frequency rank | #16,915 |
| Misspellings tracked | 10 |
| Confusable pairs | 1 |
| Source | Wiktionary (kaikki.org) |
Where “Firefox” sits in English frequency
Spelling & Dictionary Insight
The English entry for Firefox is 7 letters long, classified as a proper noun, and transcribed in the International Phonetic Alphabet as /ˈfaɪəfɒks/. Corpus data places it at rank #16,915 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. The dominant gloss from Wiktionary reads: "A free, open-source, cross-platform, graphical web browser, developed by the Mozilla Foundation.".
Our generated misspelling index lists 10 likely wrong-spelling variants for Firefox, with forms such as "ffirefox", "fierfox", and "fireffox". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 1 confusable-pair relationship, "firefly", since the words sound or look close enough that writers reach for the wrong one mid-sentence.
Etymologically, the entry records: Renamed from Firebird in 2004. The reasoning given for the name, explained as another name for the red panda (see firefox), was, “It's similar to Firebird. It's easy to remember. It sounds good. It's unique. We like it. And we weren't able to find any other… The correct English form is Firefox, spelled F-I-R-E-F-O-X.
Definition
- 1A free, open-source, cross-platform, graphical web browser, developed by the Mozilla Foundation.
Etymology
Renamed from Firebird in 2004. The reasoning given for the name, explained as another name for the red panda (see firefox), was, “It's similar to Firebird. It's easy to remember. It sounds good. It's unique. We like it. And we weren't able to find any other project or company even remotely similar to a web browser that uses the same name.” The logo depicts a fox (hence the name is equivalent to fire + fox); its original designer, Jon Hicks, has stated, “A firefox is actually a cute red panda, but it didn’t really conjure up the right imagery. The only concept I had done that I felt happy with was […] inspired by seeing a Japanese brush painting of a fox”.
Common misspellings
Also misspelled as: ffirefox,fierfox,fireffox,firefoxx,firefxo,fireofx,firfeox,firrefox,friefox,ifrefox
Misspelling Pattern Breakdown
How far each generated variant is from the correct spelling of Firefox - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
How do you spell "Firefox"?
What does "Firefox" mean?
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Using “Firefox”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is F-I-R-E-F-O-X - every other letter order is a misspelling in standard orthography.
- Say it as /ˈfaɪəfɒks/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Don't mix it up with “firefly” - see the side-by-side comparison. Firefox vs firefly
- Browse more English words and confusable pairs in the same reference. English words
Data Source
Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.