What Is Silktide? The Accessibility Platform That Publishes Its Own Price List

What is Silktide has an unusually concrete answer, because Silktide is the only vendor in this category whose complete price list is a public document.

Not on its own website. Silktide’s pricing page says only that "Every organization is different, so Silktide’s pricing depends on what you need from the platform." But a full annual rate card, with every tier and every add-on priced to the pound, sits on a UK government procurement site. If you are evaluating accessibility platforms, that single fact is worth more than any feature comparison, because it lets you calibrate every other quote you receive.

Silktide is a web governance platform. It crawls your site on a schedule, checks pages against WCAG and against content quality, SEO, privacy and uptime rules, and hands the findings to the people who can fix them. It competes most directly with Siteimprove, and the easy version of the comparison is that Silktide is the cheaper, friendlier one. That is about a third right.

This piece covers what the company is, what the product does, what it costs with real numbers, how much it actually catches, the CMS and staging picture including the thing it does that nobody else does, who it is for, and how it genuinely differs from Siteimprove.

The short version: it is roughly ten to fifteen percent cheaper than Siteimprove at the same page count, not a tier cheaper, and it unbundles analytics so that gap closes if you need both. What actually distinguishes it is transparency and reach. It publishes a more precise coverage figure than anyone else, it says out loud what a computer cannot test, and it will scan a VPN-only staging environment for a published fee.

What is Silktide, and who builds it

Silktide was founded on 27 June 2001 by Oliver Emberton, as a web design company. It left web design in 2010 and has been building web analysis tools since. The registered office is in Birmingham, England, with offices in Austin, Berlin, Copenhagen and Sydney, and the company has been remote-first since 2019.

The product lineage runs Sitescore in 2004, Nibbler in 2009, a cookie consent tool in 2012, Insites in 2016, and Silktide Monitor in 2018, which is the current platform.

Here is the structural fact that matters most and that nobody mentions in product comparisons. Siteimprove is majority owned by Nordic Capital. Acquia, which owns the former Monsido, is owned by Vista Equity Partners. Silktide appears to be bootstrapped and founder-led, with no external funding reported, at roughly 27 people.

That cuts both ways and you should say so to a client. There is no private equity clock driving repackaging and price rises. There is also a much smaller balance sheet behind a five-year public-sector contract. For a procurement team assessing counterparty risk, that is a real line item, and it is the argument a Siteimprove salesperson will make.

What the product does

Silktide describes itself as "the web intelligence company helping businesses and organizations make their websites better," and elsewhere as "an operating system for understanding websites." Its testing approach is to "explore web pages like a real person, in real browsers."

The modules cover accessibility, content quality (spelling, grammar, readability), SEO, data privacy and cookie consent, uptime monitoring, PDF accessibility and user journeys. Silktide Analytics is a separate product with separate pricing, which is the single biggest packaging difference from Siteimprove, where analytics is part of the platform conversation.

There is an AI layer, positioned as "the world’s first AI-powered web governance solution," which adds plain-language explanation to accessibility findings and suggests meta descriptions and on-page SEO improvements. Silktide’s framing of it is worth quoting because it is a swipe at the category: "We’ve watched others in our space rush out ‘features’ without performing what we would consider the requisite amount of testing prior to a launch."

We could not find a launch date for any Silktide AI feature, which is a small but real gap when a vendor is claiming a first.

The free tier is genuinely useful. The Silktide Accessibility Checker browser extension launched on Global Accessibility Awareness Day in May 2024, runs in Chrome and Edge, tests against WCAG 2.0, 2.1 and 2.2, and includes a screen reader simulator, a contrast checker and disability simulators. For a small agency doing its own quality assurance, that plus free tooling is a real practice at zero cost.

What it costs, with actual numbers

Silktide publishes nothing on its own pricing page. A complete rate card, dated April 2024, is published as a UK G-Cloud procurement document. All figures exclude VAT, and the unit is webpages monitored annually.

Silktide Analytics is priced separately by page views, from £1,470 for 500,000 views to £23,800 for 100 million.

The add-on prices are the part worth photocopying, because they tell you what the vendor thinks the hard parts cost:

Contracts run one year. The G-Cloud listing states there is no free trial, gives an overall range of £6,000 to £39,800 annually per unit, and notes that educational discounts are available.

Against Siteimprove: £5,000 is roughly $6,300 at the time of writing, against Siteimprove’s published list of about $7,100 for the same thousand pages. That is ten to fifteen percent, not a category change. And because Silktide unbundles analytics, a buyer who wants accessibility plus analytics pays £5,000 plus £1,470 at minimum, which closes the gap to near zero.

If someone tells you Silktide is the budget option, that claim survives only if you ignore what is in the box.

How much it actually catches

This is where Silktide is the best vendor in the category, and it is not close.

Silktide publishes a more precise automated coverage figure than anyone else. On a dedicated help page it states that automated checks cover 40.8% of WCAG 2.2 AA success criteria, rising to 75.5% when assisted checks are included, leaving 24.5% that requires manual testing.

Compare that with Siteimprove’s 30 to 40 percent of issues and Deque’s 57 percent by issue volume. Silktide’s number is expressed in the unit that actually matters for conformance, which is success criteria, and it is broken into three parts rather than presented as one headline.

Its plain-language explanations are better still:

"manual testing is the only way to comprehensively test every WCAG Success Criteria"

"A computer cannot tell if a title is appropriate to the content of the web page because it cannot understand the context."

And on what a perfect score means, the company answers the question a board will ask:

"If your website has scored 100% in the Index, then that means in our opinion and, according to all the unambiguous tests we perform against WCAG, you are making your site as accessible as it can be against these criteria."

One inconsistency to note, because it will confuse a careful reader. Elsewhere in the same help center Silktide says "Automated tests, whichever platform you use, will cover perhaps 30-40% of WCAG," which is the Siteimprove range rather than its own 40.8 percent. The dedicated coverage page carries the more precise figures and is the one to cite.

Manual audits are sold separately at £400 per page, which, like Siteimprove selling manual testing as a service, is a commercial admission that the scanner is not sufficient. No conformance badge is offered.

The CMS and staging picture

CMS integrations cover WordPress, Drupal 7 and 10, Adobe Experience Manager, Sitefinity, Umbraco, TERMINALFOUR, JADU and Sitevision, with custom integrations available. The behavior that matters is round-tripping: you jump from a finding into the CMS, fix it, and Silktide retests the page automatically.

There is no CI/CD story. The documented API is for recording analytics events, not for triggering scans. There is no pipeline integration, no pull request checking, and no open-source engine, which is a real difference from Siteimprove, whose Alfa engine is MIT-licensed and free. Silktide is a tool for content teams, not a tool for build pipelines, and it does not pretend otherwise.

Now the capability that decides tenders. Silktide supports HTTP authentication, custom form login, and crawler IP or user-agent adjustment for allowlisting. And beyond that:

"For an additional cost, we could even investigate setting up a VPN to VPN connection"

That cost is published on the same G-Cloud rate card: £1,640 a year.

Siteimprove cannot crawl a site that is only available on an internal network. Acquia says flatly that it is not possible. Silktide productizes it and prices it. For an agency whose client staging environments sit behind a VPN, that is the whole decision.

The limits are stated honestly, which is more than most vendors manage:

"We are not able to complete a CAPTCHA field or retrieve a code from a multi-factor authentication (MFA) method."

Login selectors have to be consistent and predictable, credentials are stored recoverably so a dummy account is required, and localhost is not reachable because the crawler is cloud-based.

Who it is for

The natural customer is a web or communications team at a mid-size public-sector or regulated organization, where a non-developer owns remediation. Councils, universities, health services, charities, financial services. Named customers include the NHS, RNIB, Santander, Accenture and the University of Oxford, and the company claims over 900 cities globally.

The smallest customer that plausibly gets value is a single-site organization at the £5,000 thousand-page tier with a dedicated communications person. There is no paid tier below a thousand pages. Below that, the free browser extension does the job and the platform is not justifiable.

Do not buy it for your own agency sites. The extension, Lighthouse, WAVE and axe DevTools cover that at no cost.

The honest comparison with Siteimprove

Three differences actually change a decision.

Transparency. Silktide’s complete rate card is a public document and its coverage figure is more precise and more honestly decomposed. Siteimprove publishes a price sheet too, on a public-sector contract page, but Silktide’s is cleaner and its coverage disclosure is better. For a buyer who has to defend a purchase, that matters.

Reach. Silktide will scan a VPN-only environment for £1,640 a year. Siteimprove will not at any price.

Scope. Siteimprove includes analytics in the platform conversation and has a broader content and search story after its MarketMuse acquisition. Silktide unbundles analytics and stays focused on governance. Which is better depends entirely on whether you want one bill or one job done.

And the counterparty question, which nobody puts in a feature table: a bootstrapped 27-person company against a Nordic Capital portfolio holding. That is not a quality judgment in either direction. It is a risk you should price.

What is not different: both are cloud crawlers that cannot see localhost, both require manual testing for a quarter of the criteria, neither runs in your pipeline, and both have users complaining about learning curve and navigation. Silktide’s G2 rating is 4.8 across 287 reviews against Acquia’s 4.5 across 157, which is a genuine signal, but its most common complaints are "complex usability" and "difficult navigation," which are the same complaints leveled at every platform in this category.

Frequently Asked Questions