sulfate vs sulphate, What's the Difference?

Which to use

“sulfate” and “sulphate” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#22,830
“sulfate” frequency rank: #47,942
“sulphate” frequency rank: 70772
confusion score

Side-by-Side Comparison

Feature	sulfate	sulphate
Definition	Any salt or ester of sulfuric acid.	Alternative spelling of sulfate.

Where the spellings diverge

Shared letters are muted; the letters that actually set sulfate and sulphate apart are highlighted. They share 6 letters in sequence, which is exactly why the eye skips the difference.

7 ch

sulfate

8 ch

sulphate

Spelling & Dictionary Insight

This is the hard kind. sulfate and sulphate are pronounced identically (/ˈsʌlfeɪt/) and both work as anoun. Neither the ear nor the grammar will rescue you; only the meaning does, so the glosses below are the whole decision. They differ by 1 letter(s) in length. Our composite confusion score for this pair is 70772, derived from the frequency rank of both members and their visual similarity.

sulfate is recorded at frequency rank #22,830, classified as anoun, pronounced /ˈsʌlfeɪt/. sulphate is at rank #47,942, tagged as anoun, pronounced /ˈsʌl.feɪt/.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 70772, this pair ranks #49,226 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of sulfate vs sulphate

Shared letters: aelstu. Private to "sulfate": f. Private to "sulphate": hp.

"sulfate" · 7 letters · shape CVCCVCV · "sulphate" · 8 letters · shape CVCCCVCV

Known mistypes of this pair

sulfate ← slufate · ssulfate · suflate · sulafte · sulfaet · sulfatte · sulffate · sulftae
sulphate ← sluphate · ssulphate · sulhpate · sullphate · sulpahte · sulphaet · sulphatte · sulphhate

Frequency comparison

sulfate#22,830

sulphate#47,942

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "sulfate" and "sulphate" be used interchangeably?

No. They are pronounced the same (/ˈsʌlfeɪt/), which is exactly why they get swapped in writing, but the dictionary meanings above are different, and pronunciation is no guide here.

Which is more common, "sulfate" or "sulphate"?

"sulfate" is the more common of the two: it sits at frequency rank #22,830 in our English list, against #47,942 for "sulphate". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering sulfate vs sulphate

The fastest way to pick the right one every time.

Read both glosses above and match the meaning you intend, only context separates this pair.
See each word in full, definition, IPA, etymology and its other confusables. Full “sulfate” entry
Browse more pairs most likely to be confused. Most confusable