The blind spot no other scanner can reach
The Industry’s Blind Spot: Payment Iframe Accessibility
Stripe Elements, PayPal, and Braintree embed payment fields inside cross-origin iframes hosted on their own domains. No external accessibility scanner can penetrate those iframes — not Deque, not Siteimprove, not accessiBe. SmarterTariff is the only tool built specifically to audit what happens inside the checkout.
Supply chain → checkout → accessibility → AI. Every broken link is a self-imposed tariff on your revenue.
What We Scan That Others Can’t
Cross-origin payment iframes are invisible to every existing accessibility tool. We built a scanner from scratch to reach inside them.
Stripe Elements Iframe Analysis
Stripe embeds card fields in iframes on js.stripe.com. We detect Stripe Elements, analyze the surrounding integration for label associations, focus management, and error handling that affect the user experience across the origin boundary.
PayPal Checkout Accessibility
PayPal buttons and Smart Payment Buttons inject their own DOM and event handlers. We verify keyboard operability, ARIA roles on interactive elements, and whether screen readers can navigate the full PayPal checkout flow.
Braintree & Adyen Payment Forms
Braintree Hosted Fields and Adyen Drop-in each use different iframe strategies. We detect the provider, map form field relationships across frame boundaries, and flag WCAG violations in labels, contrast, and target sizing.
AI Agent Checkout Simulation
AI shopping agents from OpenAI, Google, and Amazon need the same semantic structure screen readers use. We simulate an AI agent navigating your checkout to score readiness for the agentic commerce era.
Why This Matters Now
The European Accessibility Act is enforced. ADA lawsuits are surging. AI agents are arriving. Checkout accessibility is no longer optional — it’s a revenue risk.
EUR 500K
Maximum fine per violation under the EAA (Germany)
5% of turnover
EAA penalty ceiling in Italy
3,117+
ADA accessibility lawsuits filed in 2025 (27% YoY increase)
June 28, 2025
EAA enforcement date — checkout flows explicitly in scope
The AI Agent Connection
OpenAI’s Agentic Commerce Protocol, Google’s Universal Commerce Protocol, PayPal “Agent Ready,” and Amazon “Buy for Me” all break at the exact same points where screen readers fail. Missing form labels, broken keyboard navigation, absent ARIA roles — these aren’t just accessibility violations, they’re AI agent blockers. Fix accessibility and you fix AI readiness in one pass.
Frequently Asked Questions
- Why can't other accessibility scanners test payment iframes?
- Stripe Elements, PayPal buttons, and Braintree Hosted Fields all render inside cross-origin iframes hosted on their own domains (e.g. js.stripe.com). Browser same-origin policy prevents external scanners from inspecting the DOM inside those frames. SmarterTariff uses a Playwright-based headless browser with payment provider detection to analyze these flows in ways no external tool can replicate.
- What WCAG 2.2 violations are most common in payment checkout flows?
- The most frequent violations we find are: missing form labels on card number and expiry fields (1.3.1), insufficient color contrast on error messages (1.4.3), no visible focus indicators when tabbing through payment fields (2.4.7), touch targets smaller than 24x24 CSS pixels (2.5.8), and missing error identification that prevents screen readers from announcing validation failures (3.3.1).
- Does the European Accessibility Act (EAA) apply to checkout pages?
- Yes. The EAA, enforced since June 28, 2025, explicitly covers e-commerce services including the entire purchase flow. Checkout pages, payment forms, and order confirmation screens must meet WCAG 2.2 AA standards. Penalties vary by member state: up to EUR 500,000 in Germany and 5% of turnover in Italy.
- How does checkout accessibility affect AI agent commerce?
- AI shopping agents from OpenAI, Google, PayPal, and Amazon need the same semantic HTML, ARIA labels, and keyboard navigability that screen readers require. If a payment form lacks proper labels, an AI agent cannot identify the card number field. If focus management is broken, the agent cannot complete a multi-step checkout. Every accessibility failure is also an AI agent failure — fixing one fixes both.
- How long does a checkout accessibility scan take?
- A first-time scan typically completes in 30 seconds. SmarterTariff caches results so repeat scans for the same URL return in under a second. The scan covers WCAG 2.2 violations, payment provider detection, cross-origin iframe analysis, EAA compliance mapping, and AI agent readiness scoring — all in a single pass.
Stop Paying the Self-Imposed Tariff
Every inaccessible checkout is lost revenue — from customers who can’t complete payment, from EU fines you didn’t see coming, and from AI agents that fail silently. Scan your checkout in 30 seconds.
Free tier includes cached results for any URL. No credit card required.