For AI voice tools: which voice samples and docs pages bring paying users.

01How they sell

• UsageCharacters or minutes of speech metered for API customers and billed each cycle; one busy customer's month can outweigh many small plans.
• SubscriptionCreator plans with a monthly character allowance and commercial-use rights, with extra characters bought when a long project runs over.

02Payments it reads

• StripeCreator plans through Checkout and metered API billing on subscriptions; usage invoices are read with the plan.
• PolarMetered API plans billed per character or second; every cycle's usage charge is read.
• PaddleUsed for buyers in many countries who need tax handled; transactions, renewals and adjustments are read.

03Where buyers come from

• Voice library pagesA page for each voice or accent lets people hear samples and turns up in search; revenue by landing page shows which voices sell plans.
• API docsDevelopers arrive on a quickstart page, build a test integration and buy usage later; with the tag on the docs, those pages become first sources.
• Narration tutorialsYouTube videos on narrating with AI voices send creators who compare voices and buy once they've heard their own script read.
• Author groupsSelf-publishing forums share narration tips; their links arrive as referrers, or as shared links when pasted into chats.

04What Tally answers

1. Do visitors actually play the voice samples?

   Heatmaps show where people click on each page, so you can see whether the play buttons in the voice library get pressed at all; marking each play as a goal adds counts and those listeners' revenue.

   Heatmaps

2. Which voices bring the most revenue?

   In the page breakdown each voice's page carries the revenue of the visitors who landed there, so the voices that sell stand apart from the ones that only get listened to.

   Sources with revenue

3. Do API customers end up worth more than creators?

   Lifetime value by first source puts docs-driven customers beside those from YouTube, with renewals, average lifetime revenue and repeat rate for each.

   Lifetime value

4. Did that audiobook forum thread bring our biggest API customer?

   Open their first payment: the receipt lists the visits before it, the one credited, how the payment was linked and with what confidence.

   Receipts

5. Is there a picture of the whole flow from source to sale?

   Labs draws a river from first source to sale and shows visitors as an ecosystem, a quick way to see which sources feed paying customers.

   Labs

05Numbers worth watching

Lifetime value by first source

Average lifetime revenue by first source; metered API customers can grow for months, so judge channels by it rather than first payments.

Revenue by source

Revenue behind every source and landing page, which shows whether the voice library or the docs earn more.

Goal conversion

The share of visitors who play a sample, by source, if each play is sent as a goal.

06An example

07Setting up

1. StripeCreate the API plan's Checkout Session with tally_visitor_id in metadata and subscription_data, so every metered invoice keeps the source.
2. Any HTML siteAdd the tag to the docs as well as the voice library, since developers' first visits often start on a quickstart page.
3. Put data-fast-goal on each sample's play button to count plays as a goal you can compare by source.

08Questions

• Is a monthly usage bill credited to the visit just before it?

  No. A usage bill on an existing subscription is a renewal and takes the link of the first payment, so it stays with the source that won the customer.

• Can we see revenue per voice used?

  Not per voice used, since usage isn't read. Each voice page's row in the page breakdown carries the revenue of the visitors who saw it, which is the closest honest answer.

• Does consent-first mode work for visitors in Europe?

  Yes. In consent-first mode the snippet counts without a cookie until your banner calls tally('consent', true), and only then sets its first-party cookie.