The Population APISimulix builds a population of American AI agents from public Census data — for any place in the country — and answers questions about them in minutes.
We did not build this to disrupt anyone. We built it because the firms we work with told us they could no longer afford to spend $80,000 to learn which creative works. They wanted to know on Tuesday what the panels would have told them in three weeks.
— The editorsA direct-to-consumer brand came to us before their next paid-social flight. Six creative variants, four markets, one $80,000 test budget. They wanted to know which combinations would land — before lighting the budget on fire.
“You see this ad on Instagram for a $39 monthly meal kit promising ‘dinner in 12 minutes.’ Do you tap it?”
29 · Brand designer · Brooklyn, NY · 11211
20 of Jasmine’s 120+ attributes.
“Twelve minutes is the whole pitch. I’ll save it and check on payday. I’ve burned out on three meal kits already — I’m not signing up at 9 PM on a Wednesday.”
Every agent in the simulation carries this kind of shape. Demographics, household, work, consumer behavior, media diet, values — all anchored to a real place. The model writes the voice; the data decides who is in the room.
“Twelve minutes is the whole pitch. I’ll save it and check on payday.”
“$39 a month is two dinners out for our family. That’s not a meal kit, that’s a subscription I’ll forget about in three weeks.”
Killed two creatives before the flight. Reallocated $52,000 from Austin to Brooklyn and the Atlanta suburbs. Reworked the $39 price anchor in the Austin creative to “$1.30 per meal.” The campaign returned 2.3× the previous quarter’s CAC — measured against a control market they intentionally left untouched.
Each row below is a real prediction we filed publicly before the outcome was known. Updated the morning the world catches up. Methodology open at simulix.com/method.
We do not retroactively delete the bad ones. When a model misses, we publish the miss and post the recalibration that followed in the next morning’s ledger.
See the full archive →We are not the product on top. We are the population underneath. Research tools, audience platforms, agency dashboards, AI labs, political shops — they build on us. You can be running in ten minutes.
One key. Three primitives. A free tier with enough room to ship a prototype, and pricing you read on the page.
