ADA Font Size Requirements: Height, Braille, and Contrast

ADA font size requirements are not a single number. The 2010 ADA Standards for Accessible Design set minimum character heights that shift with where a sign is mounted and how far away someone reads it, starting at 5/8 inch for signs at eye level and scaling up to 3 inches or more for signs mounted high or read from a distance. Websites work under a separate framework that focuses on resizability and contrast rather than a fixed pixel size.

Minimum Character Height for Signs

Section 703.5.5 of the ADA Standards ties minimum character height to two variables: the sign’s mounting height above the floor and the viewing distance. Measurements are taken from the baseline of the uppercase letter “I.”¹

Mounted 40 to 70 inches above the floor: at least 5/8 inch (16 mm) tall when the viewing distance is under 72 inches. Beyond 72 inches, add 1/8 inch for each additional foot of viewing distance.
Mounted above 70 inches up to 120 inches: at least 2 inches (51 mm) tall when the viewing distance is under 180 inches (15 feet). Beyond 15 feet, add 1/8 inch per additional foot.
Mounted above 120 inches: at least 3 inches (75 mm) tall when the viewing distance is under 21 feet. Beyond 21 feet, add 1/8 inch per additional foot.

The scaling formula is where most errors happen. A sign hanging 10 feet up in a lobby where readers might stand 25 feet back needs characters well over 2 inches, because you keep adding 1/8 inch for every foot past the 15-foot threshold. All visual characters must sit at least 40 inches above the finished floor.¹

Raised Characters and Braille

Permanent room signs, including those for restrooms, stairwells, exits, and numbered rooms, must carry both raised characters and Braille. The rule applies to any sign labeling a room or space whose function is unlikely to change.¹

Raised characters must be between 5/8 inch and 2 inches tall, measured from the baseline of the uppercase “I.” A limited exception drops the floor to 1/2 inch when a sign carries separate raised and visual characters conveying the same information.¹ Raised characters must be uppercase, sans serif, and raised at least 1/32 of an inch from the sign surface, with smooth, rounded cross sections rather than sharp edges.²

Braille must be contracted (Grade 2) and sit below the entire raised text with at least 3/8 inch of clearance between the Braille and any tactile characters or raised borders.² Individual Braille dots must be domed or rounded, with a base diameter between 1.5 mm and 1.6 mm and a dot height between 0.6 mm and 0.9 mm. Center-to-center spacing between dots in the same cell runs 2.3 mm to 2.5 mm, and dots in adjacent cells sit 6.1 mm to 7.6 mm apart.¹

Font Style, Stroke, and Spacing

Character height alone does not make a sign readable. The standards also regulate typeface, stroke thickness, and spacing.

Visual characters on signs cannot be italic, oblique, script, or highly decorative. They must follow conventional letterforms.¹ Calligraphic and novelty fonts are effectively out.

Stroke Thickness

For raised characters, the stroke width of an uppercase “I” cannot exceed 15 percent of the character height. For visual characters the range is wider: at least 10 percent and no more than 30 percent of the character height.¹ The wider window gives designers more typeface choices for directional and informational signs that do not need raised text.

Character and Line Spacing

For visual characters, the gap between adjacent letters must fall between 10 percent and 35 percent of the character height. Line spacing between baselines of separate lines must be 135 percent to 170 percent of the character height.²

Raised character spacing uses absolute measurements. For characters with rectangular cross sections, the gap between adjacent letters must be at least 1/8 inch and no more than four times the stroke width. Characters with rounded or other cross sections require at least 1/16 inch at the base, 1/8 inch at the top, and no more than four times the stroke width.¹

Contrast and Finish

Correctly sized text still fails when it disappears into the background. Both the characters and their background must have a non-glare finish, and the text must contrast with the background using either light characters on a dark field or dark characters on a light field.¹ The standards do not fix a numerical contrast ratio for physical signs, but Access Board advisory guidance recommends at least 70 percent contrast between characters and background, calculated using the Light Reflectance Values of the two colors.

Signs That Are Exempt

Several types of signage sit outside these visual and tactile character requirements:²

Temporary signs posted for seven days or less
Building directories listing tenants or departments
Occupant names and company logos, such as a nameplate on an office door
Menus
Seat and row designations in theaters and assembly areas
Signs in non-public areas of detention or correctional facilities

A single sign can carry both exempt and regulated content. If a room sign shows a room number and an occupant name, the room number must meet all tactile and visual standards even though the name does not.²

Text Size on Websites and Apps

The ADA does not set a specific pixel size for digital text. Digital accessibility is measured through the Web Content Accessibility Guidelines (WCAG) published by the World Wide Web Consortium, which focus on whether users can resize text and whether contrast is sufficient.

WCAG 2.1 Level AA, the version most commonly referenced in ADA compliance, requires that text be resizable up to 200 percent without assistive technology and without losing content or functionality.³ A site’s layout has to hold up when text doubles in size, without clipping or overlapping. A common industry baseline for body text is 16 pixels, but the standard is about resizing, not a fixed starting point.

For color contrast, WCAG 2.1 Level AA requires a minimum ratio of 4.5:1 between normal-sized text and its background. Large text, defined as at least 18 point (about 24 pixels) or 14 point bold (about 18.66 pixels), has a lower 3:1 threshold.³

In April 2024, the Department of Justice finalized a rule requiring state and local government websites and mobile apps to conform to WCAG 2.1 Level AA under ADA Title II.⁴ Private businesses operating public accommodations under Title III still lack a formal regulation specifying a technical standard, but courts have increasingly treated WCAG 2.1 Level AA as the benchmark in ADA web-accessibility lawsuits.

Penalties for Getting It Wrong

ADA signage violations fall under Title III, which covers public accommodations. The Department of Justice can seek civil penalties in federal court, and the maximums are adjusted annually for inflation. As of the 2025 adjustment, the maximum civil penalty is $118,225 for a first violation and $236,451 for any subsequent violation.⁵ Those caps apply in DOJ enforcement actions. Private plaintiffs cannot recover civil penalties but can obtain injunctive relief and recover attorney’s fees.

Most signage disputes settle before trial. A demand letter typically leads to replacement of non-compliant signs plus payment of legal fees. The signs themselves are rarely expensive to fix; the legal costs of a compliance fight almost always run higher than getting the signage right up front.

1
Access Board. ADA Chapter 7 Communication Elements and Features
2
Access Board. Guide to the ADA Accessibility Standards – Chapter 7 Signs
3
World Wide Web Consortium. Web Content Accessibility Guidelines (WCAG) 2.1
4
Federal Register. Nondiscrimination on the Basis of Disability Accessibility of Web Information and Services of State
5
Federal Register. Civil Monetary Penalties Inflation Adjustments for 2025