How to Symbol Feet and Inches: A Clear Practical Guide

Understanding the Feet (′) and Inches (″) Symbols

The feet symbol (′) and the inches symbol (″) are typographic primes used to denote measurement in feet and inches. The standard code points are U+2032 for feet and U+2033 for inches. In plain text, many writers use the ASCII apostrophe (') and the quotation mark (") instead of the proper prime marks, but that can mislead readers or fonts that don’t map cleanly. According to All Symbols, the feet symbol is U+2032 and the inches symbol is U+2033, and these characters should be preferred in technical writing and design documentation. When you see 5′ 11″, you’re looking at typographic primes rather than simple punctuation, which improves clarity in diagrams, tables, and printed materials.

History and typography basics

The prime marks have their roots in traditional typography where the feet (prime) and inches (double prime) symbols were used by hand to denote measurements in feet and inches. Today, these marks are standardized in Unicode and are widely supported across fonts, but not all fonts render them identically. A solid understanding of “prime vs. straight quote” helps prevent misinterpretation in engineering drawings, architectural plans, and fashion patterns. The term prime designates feet, while double prime designates inches; use them consistently to avoid confusion and ensure your documents read professionally.

When to use symbols vs abbreviations

In formal technical contexts, adopt the symbols 5′ 11″ for compactness and readability. In many casual contexts, or when space is limited (like notes or mobile UI), you may prefer the abbreviations 5 ft 11 in. Be consistent within a document: if a table uses symbols, keep symbols in all rows; if you switch to abbreviations, apply that rule throughout. For accessibility and screen readers, consider including a text alternative like “five feet eleven inches” when the symbol is used in digital content. This balance preserves clarity across print and digital media.

Input options across platforms

Windows users can insert the feet and inches symbols with Alt codes or by inserting from the character map. Windows: Alt+8242 yields ′ and Alt+8243 yields ″. macOS users can access the Character Viewer (Control-Command-Space) and search for “prime” to insert U+2032 and U+2033. Linux users can type the Unicode code point with Ctrl+Shift+U 2032, then press Enter. HTML users can rely on numeric entities: ′ for feet and ″ for inches, or use the named entity ′ where supported. Always test in your target font and environment.

Unicode and encoding fundamentals

Unicode assigns a unique code point to each symbol, and UTF-8 encodes these points across bytes. For feet and inches, U+2032 and U+2033 are the standard code points. When embedding in JSON or XML, ensure proper escaping: in JSON, use the actual characters or the escaped sequence \u2032 and \u2033. If you’re rendering on the web, the entities ′ and ″ are also reliable. Maintaining consistent encoding prevents garbled symbols in multilingual documents and supports accessibility tooling.

Typography: spacing and punctuation guidelines

A core rule is to separate numbers from unit symbols with a non-breaking space to avoid awkward line breaks: 5′ 11″ rather than 5′11″ when possible. In printed work, many typesets use a thin or hair space around primes to improve legibility depending on the font. When typesetting, verify that the symbols don’t collide with neighboring punctuation and that the overall line breaks preserve the units intact. Consistency in spacing improves readability across dashboards, schematics, and textbooks.

Font considerations and glyph quality

Not all fonts render feet and inches as typographic primes. Some include the prime and double-prime glyphs that align with the design language of the font. If your document uses a sans-serif for UI or a serif for a textbook, verify the glyph shapes at the chosen size. When possible, test at the final print size and screen resolution. If a font renders the primes awkwardly, switch to a font with clear prime glyphs or adjust the font family for that section to maintain legibility.

Practical examples in documents

• In engineering drawings: 5′ 11″ is preferred for compactness and precision.
• In clothing patterns: 38 in (where space is limited) or 3 ft 2 in depending on the design spec.
• In typography and layout: 3′ 6″ can help align columns and grids when documenting dimensions.
• In code and data: store numeric measurements in a separate field and render the symbols dynamically for display, preserving data integrity while maintaining readability.

Accessibility and assistive tech

For screen readers, ensure that the textual meaning is preserved. In HTML, you can use visually hidden text to spell out the measurement when needed, or provide aria-labels that read as five feet eleven inches. When exporting to PDFs or eBooks, embed the correct Unicode glyphs so assistive technologies can interpret them accurately. Always provide a textual alternative for the symbol-heavy notation.

Industry-specific conventions

Different industries have conventions for symbols vs. words. In construction drawings, the prime symbols are standard for legibility in plans and specs. In apparel and textile catalogs, you may see both the symbol and the spelled-out measurement. In data sheets and programming documentation, prefer the symbol for visually concise specs, but include clear text equivalents for screen readers and search indexing. Consistency with industry norms helps readers interpret measurements quickly.

Common mistakes and fixes

• Mistaking the ASCII apostrophe for a prime symbol: replace with the proper U+2032 prime glyph.
• Omitting a space between the number and the symbol: add a non-breaking space to prevent line breaks.
• Mixing symbols and abbreviations in the same document: choose one approach per section.
• Using the inches symbol without distinguishing single- vs double-prime contexts: reserve inches (″) for measurement, avoid confusion with quotation marks.
• Over-using the symbols in prose: reserve symbols for measurements and spell out numbers in narrative text.

Quick-start cheat sheet and mnemonics

• Remember: feet use a single prime (′), inches use a double prime (″).
• Use NBSP between the number and the symbol: 5′ 11″.
• On Windows, use Alt codes: 8242 for ′, 8243 for ″.
• On macOS, open Character Viewer and search for prime.
• For web content, prefer ′ or ′/″ when appropriate.
• Always verify in your target font and size, and ensure accessibility with text equivalents.