Foot Abbreviation- How to Properly Abbreviate Foot

What Is the Correct Abbreviation for Foot?

The standard abbreviation for foot is ft. That's it. Two letters. No tricks.

You might also see the prime symbol (') used in some contexts, particularly in measurements. But if you're writing professionally, ft is your safest bet.

The word "foot" abbreviates to ft because it's derived from the Latin pes, but that's just trivia. What matters is knowing when and how to use it correctly.

Foot vs Feet: Does the Abbreviation Change?

No. Both "foot" and "feet" use the same abbreviation: ft.

This trips people up. They want to write "fe" or "f" for plural. Don't. The abbreviation stays constant whether you're talking about one foot or ten feet.

• 5 ft (correct)
• 5 feet (correct)
• 5' (common in informal contexts)
• 5 f (wrong)
• 5 fe (wrong)

When to Use "ft" vs the Full Word

Use ft when:

• Space is tight (data tables, technical specs, measurements)
• You're writing for an audience familiar with the context
• You're combining it with other units (5 ft 8 in, 10 ft x 12 ft)

Write out "foot" or "feet" when:

• It's the first mention in formal writing
• You're writing for a general audience
• The document style guide requires it

The Prime Symbol Alternative

You might see ' used instead of "ft" — especially in construction, real estate, or informal measurements. This comes from typesetting, where a prime mark distinguished units.

Examples:

• 6' means 6 feet
• 6' 2" means 6 feet 2 inches

This is acceptable in casual writing, blueprints, and informal contexts. But for formal documents, stick with ft.

Combining Feet and Inches

When you need to show feet and inches together, you have two clean options:

• 5 ft 8 in — spelled out abbreviations
• 5' 8" — prime and double-prime symbols

Don't mix these styles in the same document. Pick one and stay consistent.

Quick Reference Table

How to Use Foot Abbreviations in Practice

Writing Measurements

When writing dimensions, use ft with the number directly before it. No space between the number and the abbreviation:

• 10 ft ceiling
• 8 ft fence
• 12 ft ladder

Some style guides prefer a space (10 ft), others don't (10ft). Check your employer's or publisher's preference. If there's no guide, the space version is safer for readability.

Writing Height

For human height, you have options:

• 5 ft 9 in
• 5' 9"
• 5 feet 9 inches

The prime symbol version is most common in American English for personal height. International audiences may prefer metric.

Writing Area

For square footage:

• 1,500 sq ft
• 1,500 square feet

You can abbreviate "square feet" as sq ft or ft². Both are acceptable.

Common Mistakes to Avoid

• Using "f" or "ft." with a period — The abbreviation doesn't need a period. "Ft" not "Ft." or "f."
• Capitalizing it — "FT" looks like an acronym. Use lowercase "ft" unless starting a sentence.
• Using "foot" in technical contexts — Once you've established the abbreviation, use it consistently. Mixing "foot" and "ft" in the same paragraph looks sloppy.
• Forgetting the space — "The room is 10ft wide" is technically fine, but "10 ft" is more readable.

Style Guide Variations

Different style guides have different preferences:

• AP Stylebook — Uses numerals with ft (5 ft 6 in)
• Chicago Manual of Style — Accepts both numerals and words, prefers spelled-out numbers under ten
• Scientific/Technical writing — Almost always uses numerals with abbreviated units

If you're writing for a specific publication or company, check their style guide. When in doubt, consistency matters more than the specific choice.

Bottom Line

The abbreviation for foot is ft. It doesn't change for plural. Use it in technical contexts, measurements, and when space matters. Write out "foot" or "feet" in formal prose and for general audiences.

Don't overthink it. Pick a format, stay consistent, move on.