Crowdsim
Last updated 12 October 2026

Privacy at Crowdsim

Crowdsim keeps very little about people, and this page says exactly what. The crowd you see on this site is simulated: AI personas, not real people.

Who is responsible

Crowdsim is a sole proprietorship registered in Ontario, Canada. Andrew Ko is responsible for privacy. For any question or request, write to hello@crowdsim.ca.

The early-access list

When you ask for early access, we keep three things: your email address, the role you picked (a professor or instructor, at an agency, at a brand, or curious) and the date you asked.

We use them for one thing: to email you when your sim is ready. No newsletter, no marketing list, and we never sell or share the list. The list is kept until early access opens, or until you ask us to remove you, whichever comes first.

Visiting the site

  • No analytics, no advertising trackers, and no cookies of our own.
  • The site runs on Cloudflare, which keeps short-lived technical logs (such as the address a request came from) to run and protect the service.
  • The fonts load from Google Fonts, so your browser asks Google for them and Google sees that request.

Apps that use the Crowdsim API

Apps with an API key send decisions to the engine: an ad's wording, a budget, targeting, and sometimes their own campaign numbers.

  • Used to answer the call. The ad and the decision are read so the crowd can react to them.
  • Stored so a repeat is free. Each answer is kept, so the same request gets the same answer again without running twice. Stored answers can include parts of the ad's wording.
  • Never used to teach the crowd. The crowd learns only from the real world: the news, published figures, and what people are saying in public. Your ads and plans get a reaction and nothing more.
  • No personal information, please. The API refuses requests with fields for people's names, email addresses or ID numbers. Send the work, not the people who made it.

To read an ad and write the crowd's reactions, the engine sends the text to Anthropic, which provides the Claude models. Under its commercial terms, Anthropic doesn't use that text to train its models.

What the crowd reads

Each week the crowd reads a pulse: dated, sourced signals from news, published figures, and public YouTube comments and Bluesky posts about the industry. Comments and posts are read in aggregate for that one run and never stored. The pulse keeps only themes and roughly how many people raised them, and links to a video or a search page, never to a person's post or name.

Where it is kept

Everything Crowdsim stores is kept with Cloudflare. Text sent to the models goes to Anthropic. Both may process it outside Canada, including in the United States, where it is subject to the laws there.

Your choices

Changes

If this changes, the date at the top changes with it. If we ever want to use your information in a new way, we'll ask first.