AdAlign vs Optimizely: Experiment Programme or Per-Ad Check

No experiment report tells you which of your live ads lands on a page that contradicts it. AdAlign scores every one. If you run an experimentation programme on Optimizely and spend between €250,000 and €750,000 a month on Meta and Google Ads, keep Optimizely and add AdAlign's Portfolio band. It starts at €2,490 a month on an annual contract billed monthly (AdAlign pricing, checked on 27 October 2026). Start with the free audit on a single ad. Choose Optimizely on its own when the job is the programme itself: A/B, multi-page, feature and server-side tests on its Stats Engine, priced through a custom quote (Optimizely plans).

Disclosure: I earn a commission if you buy AdAlign through a link on this page, and this page recommends it. Every claim about AdAlign links to AdAlign's own pages.

Before procurement starts:

1. Work out what one test costs in traffic. For example, Optimizely's sample size calculator, at its default 3% baseline, 20% minimum detectable effect and 95% significance, asks for 13,000 visitors per variation. Two variations need 26,000. A landing page with 6,500 paid visitors a week needs 26,000 / 6,500 = 4 weeks. If the ad feeding that page scores below 5 against it, those four weeks are also four weeks of spend at risk.
2. Start from the tags your ads already carry. Optimizely's documentation names targeting an experiment at visitors from an ad campaign as the most common use of query strings. It also says manual UTM tags transfer to it better than a Google click ID alone (Optimizely docs). If your ads carry no manual tags, fix that before scoping any ad-specific test.
3. Take the baseline the board will ask for. Spend at risk per landing page from AdAlign before the first test, and the same figure after the winning variant ships (how it works).

Two different scales of problem

Optimizely sells a platform. An agentic CMS with native testing, experimentation with its proprietary Stats Engine and warehouse-native analytics, and an agent platform with built-in evaluation and governance (Optimizely plans). Its unit is the experiment.

AdAlign's unit is smaller: one ad, the page it opens, and a score out of 10. It reads every live Meta and Google ad through a read-only connection and compares each with its landing page on four dimensions. Then it rolls the results up per page and ranks pages by what their low scorers keep spending (how it works). Count both in your own accounts: live experiments against live ads. The larger number is where a mismatch hides.

Documented, side by side

Three decisions that separate them

Programme or pair

"Which version of the checkout converts better across six markets" is Optimizely's question, with feature flags and server-side tests behind it. A programme like that is built for the questions someone thought to ask. "Which live ads send people to a page that has stopped saying what the ad says" is not one of them. Nobody sets up an experiment for a mismatch they have not noticed. AdAlign names the weakest dimension on each pair: visual match, message match, above-the-fold continuity or tone.

Who picks the landing page

You picked it. On Google, the platform can overrule you. Final URL expansion is on by default once you opt into AI Max for Search. Google may then replace your final URL with a page it judges more relevant, and write a headline to match (Google Ads Help). The default favours Google's view of what converts over the page you chose. An Optimizely experiment scoped to your URL never sees the visitors sent elsewhere. Which of your search ads went to a page you never chose? Google's landing pages report lists those pages with a Selected by column (Google Ads Help). Put each one through AdAlign's audit.

What security review will ask

AdAlign's FAQ says it is working toward SOC 2, not that it holds it. It runs on Supabase, which is SOC 2 Type II certified, and Vercel, with encryption at rest and in transit (FAQ). Ad content and landing page data are stored, anonymised, to build benchmarks. Its Google Ads connection uses the AdWords scope on a read-only basis, and disconnecting purges synced data within 30 days (privacy policy). Put those lines in front of your security team on day one, not in week six.

What it costs

Optimizely publishes no prices. Its plans page asks for goals and requirements and returns a quote (plans). AdAlign publishes its bands, checked on 27 October 2026 on its pricing page. Scale is from €1,290 a month for €75,000 to €250,000 of monthly ad spend. Portfolio is from €2,490 for €250,000 to €750,000, and Enterprise is custom above that. All are annual contracts billed monthly, excluding VAT, with seats and ad accounts unlimited. Every plan starts with a €1,500 paid pilot that comes off the first invoices if you continue. Portfolio adds dedicated onboarding and a quarterly review with the founder.

Choose AdAlign if

• Your job is checking that every live ad, across brands, markets and agencies, still lands on a page that keeps its promise.
• You want the check running daily, with alerts to email or Slack when a score drops (how it works).
• You need a figure per landing page that procurement can weigh against the band price.

Choose Optimizely if

• Your job is running an experimentation programme: A/B, multi-page, feature and server-side tests, read through warehouse-native analytics.
• Your content already lives in Optimizely's CMS, which lists native testing and personalisation.
• The change you need is structural, not a headline or call to action.

At this size the answer is usually both. Optimizely decides which page wins. AdAlign checks that every ad still points at a page worth testing.

Free steps before the first sales call

Three free checks settle most of the argument. First, run the free audit on your five highest-spend ads; a free account gives the full breakdown for 5 audits a month. Second, open Google's landing pages report for any AI Max or Performance Max campaign and list the pages Google selected. Third, put your traffic through Optimizely's sample size calculator, so you know how long a test on each page would run. If the audits come back below 5, AdAlign, which pays me a commission, is the next call. Book the demo to have one account scored on the call, then the pilot. Product background sits in the AdAlign glossary entry.

FAQ

Can Optimizely target a test at visitors from one ad?

Yes, through an audience condition on a query parameter. Its documentation notes that utm_content differentiates ads or links that point to the same URL (Optimizely docs). So give each ad its own value.

Does AdAlign need anything installed on our site?

Not for scoring. It reads the ad accounts and captures each page the way a visitor sees it (audit). Only Variants needs the AdAlign tag on your domain, and nothing publishes until someone on your team does it (how it works).

Does AdAlign score pages built in Optimizely's CMS?

Yes. AdAlign scores every live ad against the page it points to, wherever that page is hosted (compare). A page in Optimizely's CMS is scored like any other.