Questions about Lens, answered.

Lens starts with one short snippet in your site's <head>. Copy it from the dashboard and paste it where your platform takes custom code: a theme setting in WordPress or Shopify, the custom code panel in Webflow, a Custom HTML tag in Google Tag Manager, or your template if you write your own HTML. That is the only technical step.

Lens then checks the live page, confirms the site ID and waits for the first request. When it arrives, the dashboard tells you the site is live.

The tag ships with a short style rule that hides headings and paragraphs for up to three seconds while Lens decides which version to show. Visitors who are not part of a campaign see your original page as soon as Lens answers. If Lens cannot answer, the original appears when the three seconds are up.

Give Lens the pages your ads point at. It fetches them and lists the text blocks it can change: headlines, subheads, body paragraphs, buttons and captions, each with its role.

You pick which blocks a campaign may rewrite. Footers, legal text and cookie notices are protected automatically, and a developer can fence off anything else by adding data-foundry-protect to it.

Three UTM values: utm_source, utm_medium and utm_campaign. Paste the full URL from one of your ads and Lens reads them out of it (plus utm_term and utm_content when they are there) and suggests a short description of who the campaign is for. Edit the description until it sounds like the person you are paying to reach.

Those three values are how a visitor is matched to the campaign later, and the match is exact. This is what a tagged link looks like:

yoursite.com/pricing?utm_source=linkedin&utm_medium=paid-social&utm_campaign=multi-clinic-staff-scheduling

For every block you allowed, Lens writes two options aimed at the audience you described. Keep one, edit it, write your own or keep the original. Regenerate an option if neither is close.

Nothing is published until you publish it. The copy you approve is the only copy a campaign visitor can see.

Your original page. A visitor who arrives without UTMs is never matched, so your organic traffic always sees the original. Search crawlers arrive the same way, so they see the original too.

Google knows the exact phrase that triggered your ad, and ValueTrack parameters let you drop it into the URL. Lens picks the campaign from utm_source, utm_medium and utm_campaign. If utm_term carries the keyword, Lens uses it to tune the wording inside that campaign's copy.

Job title, function, seniority, industry and company size all live inside Campaign Manager. When someone clicks, your site receives none of it, only the URL. So the audience has to travel in the link: build one campaign per audience and give each its own utm_campaign. In Lens you describe that audience in plain words, and the copy options are written for them.

Most Meta accounts separate audiences at the ad set level: a cold interest audience in one, a lookalike in another, recent site visitors in a third. Lens matches on utm_campaign, not on the ad set, so ad sets inside one campaign share one version of the page. When a retargeting audience and a cold audience need different words, and they usually do, put them in separate campaigns.

Add each client's website as its own site in one Lens account and switch between them from the dashboard. How many sites one account holds depends on the plan. The holdback rate is set per site, so every client gets their own control group, and their results never mix with another client's.

The usual way to judge a copy change is to compare this month with last month. That comparison mixes your change with everything else that moved: budgets, seasons, a competitor going quiet, a sale ending.

A holdback removes most of that. Lens assigns each campaign visitor to one of two groups when they first arrive. The control group keeps seeing the original page. Both groups arrive from the same ads at the same time, so the copy is the main thing that differs between them.

You set the holdback rate for the site, anywhere from 0 to 20% of campaign visitors. A bigger control group gives you a steadier baseline sooner. A smaller one shows more visitors the campaign copy.

Yes. Assignment is decided from a random visitor id stored in the visitor's browser, so a person who comes back sees the same version they saw the first time.

Lens counts conversions on your page rather than trusting each ad platform's own numbers, so both groups are measured with the same ruler. It recognizes common conversions without setup: form submissions, clicks on calls to action and clicks through to tools such as Calendly, HubSpot or Intercom. For anything else, one call does it:

window.__lensInstance.trackConversion('purchase')

Lift is the difference between the two groups' conversion rates, as a share of the control group's rate. The dashboard shows the rates, the visitor counts behind them and the lift for each campaign once its control group has visitors.

Lens shows those numbers as they are. It does not run a significance test for you, so read a small sample with care: with a few dozen visitors in the control group, one or two conversions either way can swing the lift a long way. Give a campaign enough traffic, and enough days, before you act on its number.

The holdback also tells you when the campaign copy is not helping. If the control group converts as well or better, keep the original and try a different angle.

A free checklist built from your own answers. You answer eleven questions about where your ads run, your links, your landing page and how you measure. Anything not fully in place becomes a step, with what you do and what Lens does. Anything already in place is listed as done.

There is no score and no signup. The plan is built in your browser, and nothing is sent anywhere unless you ask us to email it to you.

Nothing. The free plan needs no card, and you only enter payment details when you upgrade. The pricing page lists what each plan covers.