ReducedMotionPriority [fact] v1.0.0

A meaningful share of users — between 5% and 30% depending on segment — have prefers-reduced-motion: reduce enabled at the OS level, either by default (older devices, certain accessibility profiles) or by deliberate choice.

Between approximately 5% and 30% of users have prefers-reduced-motion: reduce enabled — driven by vestibular disorders, migraine, motion-induced nausea, epilepsy risk, deliberate battery / focus preference, and OS defaults on certain device classes — making reduced-motion compliance a non-niche concern.

Meta

• License: Apache-2.0
• License Provenance: package-authorship-claim

Confidence

strong

Applies To

• decision to gate any animation behind prefers-reduced-motion
• estimating coverage and compliance cost for animation work
• QA testing matrix (must include reduce-motion ON pass)

Quantitative

• Estimated Share: 5%–30% depending on user segment
• High End Segments: older users, users with chronic migraine, vestibular patients
• Motion Sensitivity Population Estimates: ~35% of adults experience some form of motion sensitivity (NIH)

Counter Conditions

• Exact rates are hard to measure — the OS preference is queryable but not commonly reported in analytics.
• Lower bound (5%) reflects users who explicitly toggle the setting; upper bound (30%) includes default-on configurations and users who would benefit but haven't toggled.
• Younger / mobile-only segments tend toward the lower bound; aging / desktop / accessibility-aware segments toward the upper.

ReducedMotionPriority [fact] v1.0.0

A meaningful share of users — between 5% and 30% depending on segment — have prefers-reduced-motion: reduce enabled at the OS level, either by default (older devices, certain accessibility profiles) or by deliberate choice.

Between approximately 5% and 30% of users have prefers-reduced-motion: reduce enabled — driven by vestibular disorders, migraine, motion-induced nausea, epilepsy risk, deliberate battery / focus preference, and OS defaults on certain device classes — making reduced-motion compliance a non-niche concern.

Meta

• License: Apache-2.0
• License Provenance: package-authorship-claim

Confidence

strong

Applies To

• decision to gate any animation behind prefers-reduced-motion
• estimating coverage and compliance cost for animation work
• QA testing matrix (must include reduce-motion ON pass)

Quantitative

• Estimated Share: 5%–30% depending on user segment
• High End Segments: older users, users with chronic migraine, vestibular patients
• Motion Sensitivity Population Estimates: ~35% of adults experience some form of motion sensitivity (NIH)

Counter Conditions

• Exact rates are hard to measure — the OS preference is queryable but not commonly reported in analytics.
• Lower bound (5%) reflects users who explicitly toggle the setting; upper bound (30%) includes default-on configurations and users who would benefit but haven't toggled.
• Younger / mobile-only segments tend toward the lower bound; aging / desktop / accessibility-aware segments toward the upper.

Sources

Relations

related: [@community/constraint-reduced-motion, @community/constraint-animation-pref-respected, @w3c/source-wcag-22]

Meta

• License: Apache-2.0
• License Provenance: package-authorship-claim

Confidence

strong

Source

• Eric Bailey & Sara Soueidan, 'Designing Safer Web Animation For Motion Sensitivity' (Smashing, 2020)
• Val Head, 'Designing With Reduced Motion For Motion Sensitivities' (Smashing, 2020)
• WebAIM Screen Reader User Survey #9 (2021) — accessibility-feature usage data
• Apple — vestibular disorder accessibility documentation

Applies To

• decision to gate any animation behind prefers-reduced-motion
• estimating coverage and compliance cost for animation work
• QA testing matrix (must include reduce-motion ON pass)

Quantitative

• Estimated Share: 5%–30% depending on user segment
• High End Segments: older users, users with chronic migraine, vestibular patients
• Motion Sensitivity Population Estimates: ~35% of adults experience some form of motion sensitivity (NIH)

Counter Conditions

• Exact rates are hard to measure — the OS preference is queryable but not commonly reported in analytics.
• Lower bound (5%) reflects users who explicitly toggle the setting; upper bound (30%) includes default-on configurations and users who would benefit but haven't toggled.
• Younger / mobile-only segments tend toward the lower bound; aging / desktop / accessibility-aware segments toward the upper.