Incrementality you can act on, every day.
Stella turns every spend change into an automated causal study, then gives you daily incremental iROAS and response curves per campaign and channel. Insight to action in days, not the month a holdout takes.
- ✓Daily incremental iROAS per campaign and channel, with confidence bands.
- ✓Automated before-and-after causal studies on every qualifying spend change.
- ✓Most powerful when calibrated by your holdouts and MMMs, it inherits their accuracy.
Included from Professional ($3,000/mo) and up.
Trusted by growth teams who left enterprise measurement vendors






Your incrementality is moving. A quarterly read cannot keep up.
Creative fatigues, audiences saturate, and competitors shift. The iROAS that was true in January is not true today. A holdout gives you a rigorous snapshot, but you make budget decisions every week. Always-On tracks how incremental each channel is, daily, so the number you act on is the one that is true right now.
Every spend change becomes a causal study.
When a campaign meaningfully changes spend, Stella runs a 15-day before-and-after causal analysis, controlling for your other spend and confounders. The change only qualifies if the window is clean, with no other change within a few days, so each read stays uncontaminated. A lite Bayesian model sets the baseline at the campaign level and rolls up to the channel.
Automated reads count a little. Your holdouts anchor the truth.
An automated study on its own is directional, so Stella weights it low. Your calibrated MMMs count more, and your rigorous holdouts anchor the result. Always-On is most powerful when calibrated by those, because it inherits their accuracy between tests instead of guessing on its own.
Recent studies are weighted higher, so accuracy compounds as you keep testing.
The more you test, the more accurate it gets.
Recent studies are weighted higher, so accuracy compounds as you keep running holdouts and MMMs. Stella keeps two years of studies on hand and reweights continuously, so the daily number is always anchored to your most recent rigorous evidence.
Response curves per campaign and channel, every day.
See where each campaign and channel saturates, targetable to Shopify revenue, Amazon revenue, or total. You know which channels still have headroom to scale and which to pull back, this week, not next quarter.
Daily, transparent, cross-platform.
Cross-platform incrementality
See how incremental Meta is on Shopify versus Amazon versus your total business, not a single blended number that hides the difference.
Campaign up to channel
Measure each campaign, then roll up hierarchically to the channel, so you can act at whichever level the decision lives.
Full transparency
Every automated study and its confidence band is visible, with two years of history. Nothing is hidden behind a single confident number.
Hear it from the brands we run measurement for.
Always-On is included from Professional ($3,000/mo) and up.
Have us run it, or run it yourself.
Most brands want measurement done for them. That's our consultancy, and it's where most clients start. Not ready for done-for-you? The same platform is self-serve, from $6,000 down to free. There's an option for everyone.
$10k isn't for everyone. There's a plan for every budget.
Prefer to run it yourself? Same platform, self-operated: the full loop at $6,000, always-on incrementality from $3,000, attribution and surveys from $750, or start completely free. Walk down to the plan that fits.
- ✓Two media mix models and two holdout analyses every month
- ✓Upload a spreadsheet, get a real model back. No connectors to set up.
- ✓The same models we run for enterprise brands, not spreadsheet math
- ✓Ask questions about your results in plain English
- ✓Multi-Touch Attribution: see every touchpoint that leads to a sale
- ✓Ask buyers how they found you, right after they check out
- ✓Connect up to 5 sources (Shopify, Amazon, Meta, Google, TikTok) and stop pulling reports by hand
- ✓Run as many holdout tests and media mix models as you want, on data you upload
- ✓Ask questions about your results in plain English
- ✓Everything in Starter
- ✓Always-On Incrementality: a live view of how incremental every campaign is, updated daily, with no test to run
- ✓Holdouts and media mix models run straight off your connected data, region by region. Up to 7 sources, no more uploads.
- ✓See where the next dollar should go, and where a channel is already saturated
- ✓Ask your data questions from Claude, ChatGPT and your other AI tools
- ✓Everything in Professional
- ✓We send incremental conversions back to Meta, Google, TikTok and more, so their algorithms optimize for real profit instead of last click
- ✓All of your Stella data delivered into your own warehouse
- ✓Unlimited data sources
Always-On incrementality questions, answered.
How does a spend change qualify for a study?
When a campaign meaningfully changes spend, Stella runs a 15-day before-and-after causal analysis, controlling for your other spend and confounders. The change only qualifies if the window is clean, with no other change within a few days on either side, so each read is not contaminated by something else moving at the same time.
Is automated measurement as accurate as a holdout?
On its own, an automated read is directional, which is why Stella weights it low. It becomes powerful when calibrated by your holdouts and MMMs: those rigorous results anchor the truth, and Always-On inherits their accuracy between tests. The more you test, the more accurate the daily numbers get.
Do I get results per campaign or per channel?
Both. Stella measures incrementality at the campaign level with a lite Bayesian model, then rolls campaigns up hierarchically to the channel level, so you can act on a single campaign or see the whole channel.
Which outcomes can I measure?
Target the response to Shopify revenue, Amazon revenue, or total revenue, so you can see how incremental Meta is on Shopify versus Amazon versus your blended business, not just one platform.
How fast is it compared to a holdout?
A geo holdout takes 20 days or more before you get a read. Always-On produces daily incremental iROAS and response curves continuously, so you move from insight to action in days. Run holdouts for the gold-standard number, and let Always-On keep it fresh in between.
What plan includes Always-On?
Always-On Incrementality is included from Professional ($3,000/mo) and up. Incrementality testing and media mix modeling are in every plan, free and up.
See your daily incrementality.
Book a strategy call and we will show you what Always-On surfaces on your channels, calibrated by the holdouts and MMMs you already run.