axe DevTools vs Siteimprove

From $40 per user/month (indicative, Pro)

Quote on request

Free extension covers a lot. Pro adds guided manual testing; enterprise plans are quote-based.

Enterprise annual contracts priced by pages crawled and modules.

Free browser extension with the core axe-core rule set.

Free browser extension for single-page checks.

Widely used

Deque Systems · since 2015

Widely used

Siteimprove · since 2003

• Guided manual testing addresses the two thirds of WCAG that scanners cannot.
• Findings come with concrete code-level remediation advice.
• Deque's accessibility expertise is the deepest in the industry.

• Scans entire large sites and assigns findings to content owners, not just developers.
• Combines accessibility with SEO and content quality in one governance view.
• Reporting suited to demonstrating compliance progress to executives and regulators.

• Per-seat pricing adds up across a large engineering organisation.
• The free extension is good enough for many teams, blurring the upgrade case.
• Enterprise deployment needs process design, not just a licence.

• Expensive and aimed at organisations with a governance function.
• Weak fit for application testing as opposed to content sites.
• Limited shift-left developer tooling compared to Deque.

Organisations with a formal accessibility programme and compliance obligations.

Universities, government and large content organisations with legal accessibility obligations.