See your site through the eyes of someone with a disability.

empathy_audit goes beyond WCAG compliance checks. It simulates real people with motor tremors, vision loss, ADHD, and other conditions. You see where they struggle and where they quit. Each issue includes specific fix guidance.

Quick Start

{
  "url": "https://example.com/checkout",
  "personas": ["motor-tremor", "low-vision", "cognitive-adhd"],
  "task": "Complete a purchase"
}

What happens:

Each disability persona attempts the task.
Their impairments change how they interact. Tremor causes missed clicks. Low vision makes small text unreadable.
WCAG violations are detected and mapped to real user impact.
You get step-by-step fixes for each issue.

Parameters

Parameter	Type	Required	Default	Description
`url`	string	Yes	—	Page to audit
`personas`	array	No	All	Disability personas to simulate
`task`	string	No	General exploration	Specific task to attempt
`wcagLevel`	string	No	`AA`	WCAG level: `A`, `AA`, `AAA`
`depth`	number	No	1	Pages to crawl

Disability Personas

`motor-tremor`

Simulates: Essential tremor, Parkinson's, cerebral palsy, repetitive strain injury.

How this persona behaves:

Mouse movement is imprecise with jitter
Small click targets fail repeatedly
Hover menus close before the cursor arrives
Double-clicks happen by accident
Keyboard navigation is strongly preferred

Common barriers found:

Barrier	WCAG	User Experience
Small click targets	2.5.5	8 attempts to click a 24px button
Hover-dependent menus	2.1.1	Menu closes before cursor reaches it
Time-limited forms	2.2.3	Session expired during slow typing
No keyboard shortcuts	2.1.1	Forced to use mouse for everything

`low-vision`

Simulates: Macular degeneration, glaucoma, cataracts, partial sight.

How this persona behaves:

Uses 200-400% browser zoom
Relies on high contrast
Loses page context when zoomed in
Cannot read small text or icons
Needs clear visual hierarchy

Common barriers found:

Barrier	WCAG	User Experience
Fixed-width containers	1.4.10	Content cut off at 200% zoom
Low contrast text	1.4.3	Cannot read gray-on-white body text
Icon-only buttons	1.1.1	No idea what the hamburger menu does
Tiny form labels	1.4.4	Cannot tell which field is which

`cognitive-adhd`

Simulates: ADHD, executive function challenges, attention difficulties.

How this persona behaves:

Scans rapidly without reading fully
Clicks impulsively, sometimes hitting wrong targets
Abandons long forms or multi-step flows
Gets distracted by movement and animation
Loses track of progress in multi-step flows

Common barriers found:

Barrier	WCAG	User Experience
Wall of text	3.1.5	Glazed over and missed key info
Auto-playing video	2.2.2	Could not focus on the form
No progress indicator	3.3.4	Did not know how many steps remained
Long forms	3.3.2	Abandoned at field 12 of 20

`dyslexia`

Simulates: Reading difficulties, letter reversal, word recognition challenges.

How this persona behaves:

Reads slowly
Misreads similar words (their/there, form/from)
Struggles with justified text
Benefits from icons next to text
Needs generous line spacing

Common barriers found:

Barrier	WCAG	User Experience
Justified text	Best practice	Letters swim, lost place
Dense paragraphs	1.4.12	Could not parse the content
Ambiguous labels	3.3.2	Confused "Email" for "E-mail" link
Poor font choice	Best practice	Letters hard to tell apart

`deaf`

Simulates: Deaf, hard of hearing, auditory processing disorder.

How this persona behaves:

Cannot hear audio content
Misses audio alerts and notifications
Depends entirely on visual information
Needs captions or transcripts
May need sign language

Common barriers found:

Barrier	WCAG	User Experience
Video without captions	1.2.2	Missed entire product demo
Audio-only alerts	1.4.2	Did not know an error occurred
Phone-only support	Best practice	No way to get help

`color-blind`

Simulates: Protanopia, deuteranopia, tritanopia, and other color vision gaps.

How this persona behaves:

Cannot distinguish red from green (most common)
May confuse blue and yellow (less common)
Depends on patterns, labels, and position
Struggles with color-coded status indicators

Common barriers found:

Barrier	WCAG	User Experience
Red/green validation	1.4.1	Cannot tell which fields have errors
Color-only charts	1.4.1	Graphs are meaningless
Status indicators	1.4.1	All traffic lights look the same

Output

{
  "url": "https://example.com/checkout",
  "wcagLevel": "AA",
  "personas": {
    "motor-tremor": {
      "taskSuccess": false,
      "abandonmentPoint": "Payment form - credit card expiry dropdown",
      "timeToAbandon": 142,
      "attempts": {
        "clicks": 47,
        "missedClicks": 23,
        "successfulClicks": 24
      },
      "barriers": [
        {
          "type": "small-target",
          "element": "#expiry-month",
          "wcag": "2.5.5",
          "severity": "critical",
          "targetSize": "32x24",
          "requiredSize": "44x44",
          "userImpact": "Required 8 attempts to click, user patience exhausted",
          "remediation": {
            "summary": "Increase dropdown trigger to 44x44px minimum",
            "code": "<select style='min-width: 44px; min-height: 44px;'>",
            "effort": "low"
          }
        }
      ]
    },
    "low-vision": {
      "taskSuccess": true,
      "timeToComplete": 287,
      "zoomLevel": "200%",
      "barriers": [
        {
          "type": "low-contrast",
          "element": ".help-text",
          "wcag": "1.4.3",
          "severity": "moderate",
          "contrastRatio": "3.2:1",
          "requiredRatio": "4.5:1",
          "userImpact": "Couldn't read CVV help text, had to guess format",
          "remediation": {
            "summary": "Increase text contrast to 4.5:1",
            "code": "color: #595959; /* was #999999 */",
            "effort": "low"
          }
        }
      ]
    }
  },
  "summary": {
    "totalBarriers": 7,
    "critical": 2,
    "serious": 3,
    "moderate": 2,
    "wcagViolations": {
      "A": 1,
      "AA": 4
    },
    "recommendations": [
      "Increase all interactive targets to 44px minimum",
      "Add keyboard navigation to dropdown menus",
      "Improve contrast ratio on help text",
      "Add visible focus indicators"
    ]
  }
}

Use Cases

1. Pre-Launch Accessibility Review

Before launching a new feature, run empathy audits on all disability personas.

{
  "url": "https://staging.example.com/new-feature",
  "personas": ["motor-tremor", "low-vision", "cognitive-adhd", "deaf", "color-blind"],
  "task": "Complete the new onboarding flow"
}

2. Prioritizing Accessibility Fixes

You have 100 WCAG violations. Which ones matter most?

{
  "url": "https://example.com",
  "depth": 5
}

The audit shows which violations caused users to leave. It also shows which ones were minor. Fix the critical ones first.

3. Compliance Documentation

Need evidence for a VPAT or accessibility statement? Use this.

{
  "url": "https://example.com",
  "wcagLevel": "AA",
  "depth": 10
}

This generates detailed barrier reports with WCAG mappings.

Perceptual Transport Analysis (v18.26.0)

The empathy audit now includes Wasserstein-based perceptual transport analysis. It is the first tool that measures how much visual information each persona loses.

How It Works

Screenshot Capture -- Takes a screenshot during the audit.
Persona Visual Filter -- Applies the persona's visual filter:
- Low vision: Blur plus contrast reduction
- Color blind: Color channel changes (simulates deuteranopia)
- Elderly: Yellowing lens, mild blur, and contrast loss
Wasserstein Distance -- Measures the gap between the original and filtered images.
Metrics -- Reports information loss, motor cost, cognitive load, and attention mismatch.

Perceptual Metrics

Metric	What It Measures	Example
Information Loss	Visual content the persona cannot see (0-100%)	1.1% on good sites. 15%+ on color-dependent ones.
Motor Cost	How hard interactive elements are to reach (0-100%)	100% for motor-impaired (3x effort). 0% for cognitive.
Cognitive Load	How overwhelming the visual layout is (0-100%)	70% for ADHD. 20% for color-blind.
Attention Mismatch	How far focus strays from design intent (0-100%)	60% for ADHD (drawn to motion). 10% for deaf.
Transport Distance	Raw Wasserstein distance: original vs. filtered	Higher values = more visual information lost.

Why Scores Differ Per Persona

Each persona has different barrier severity multipliers. The same page produces different scores.

Barrier Type	Motor	ADHD	Low Vision	Color Blind	Dyslexic	Deaf	Elderly
Touch targets	3.0x	0.5x	1.5x	0.5x	0.5x	0.5x	2.0x
Cognitive load	0.8x	3.0x	1.0x	0.8x	2.5x	0.8x	2.0x
Low contrast	0.5x	0.8x	3.0x	2.0x	1.5x	0.5x	2.5x
Color-only info	0.3x	0.5x	2.0x	3.0x	0.8x	0.5x	1.5x
Timing	2.0x	2.5x	1.5x	0.5x	1.5x	1.5x	2.0x
Missing labels	1.5x	1.5x	2.0x	1.0x	2.0x	1.0x	2.0x

The final score blends barrier-weighted scoring (70%) with perceptual transport analysis (30%).

Example Response

{
  "persona": "color-blind-deuteranopia",
  "empathyScore": 57,
  "empathyScoreBarrierOnly": 42,
  "perceptualTransport": {
    "informationLoss": 0.011,
    "attentionMismatch": 0.1,
    "motorCost": 0,
    "cognitiveLoad": 0.2,
    "perceptualScore": 93,
    "transportDistance": 0.0038,
    "computeTimeMs": 450
  }
}

Mathematical Foundation

This uses Sliced Wasserstein Distance from optimal transport theory. It measures the minimum cost of transforming one visual distribution into another.

A persona's visual filter simulates their impairment. The Wasserstein distance from the original measures information loss. This goes beyond "does it pass WCAG." It answers: "how different does this page look through their eyes?"

Based on Agueh & Carlier (SIAM 2011) and Multiscale Sliced Wasserstein as Perceptual Color Difference (ECCV 2024).

Why This Is Different

WCAG Checker	Empathy Audit	Empathy Audit + Perceptual Transport
"Button has no accessible name"	"Blind user could not proceed -- 'Next' button had no label"	Same, plus: "persona loses 12% of visual info"
"Contrast ratio is 3.2:1"	"Low-vision user at 200% zoom could not read the error"	Same, plus: "Wasserstein distance 0.045"
"Target size is 32px"	"Tremor user failed 8 click attempts, then quit"	Same, plus: "motor cost 100% (3x effort)"
Counts violations	Predicts when users leave	Predicts abandonment + measures info loss
Compliance-focused	User-experience-focused	User-perception-focused

CI/CD Integration

# Fail build if critical accessibility barriers found
npx cbrowser empathy-audit https://staging.example.com \
  --task "Complete checkout" \
  --fail-on critical \
  --output accessibility-report.html

Related Tools

cognitive_journey_autonomous -- Full journey simulation
agent_ready_audit -- AI agent friendliness
UX Analysis Suite -- Full UX analysis capabilities

Last updated: v18.9.0

Tool Empathy Audit

Quick Start

Parameters

Disability Personas

`motor-tremor`

`low-vision`

`cognitive-adhd`

`dyslexia`

`deaf`

`color-blind`

Output

Use Cases

1. Pre-Launch Accessibility Review

2. Prioritizing Accessibility Fixes

3. Compliance Documentation

Perceptual Transport Analysis (v18.26.0)

How It Works

Perceptual Metrics

Why Scores Differ Per Persona

Example Response

Mathematical Foundation

Why This Is Different

CI/CD Integration

Related Tools

From the Blog