Demio: what does its API report, and when?
Everything eventually, and almost nothing as it happens. That is a real constraint and a smaller one than it sounds.
Demio’s official API documents no webhooks. Registration and join events reach an outside system only through Zapier, whose four Demio triggers are polled rather than instant, and none of the four covers leaving. The only departure signal anywhere on the platform is a “left early” status inside the participants report you pull once the session has ended. The registration form does carry a phone number, which is the one thing nothing works without.
Does Demio have webhooks an outside system can subscribe to?
No. The public API is a small read-and-write surface — events, event dates, a registration call and a participants report — with no webhooks section in it, and the two integration layers most people would reach for next confirm the shape rather than fixing it. Demio’s own help centre lists exactly four Zapier triggers[1], none of them marked instant, and Make.com’s Demio app is a list of action modules[2] — create a registration, get an event, list events, list participants — with no trigger among them.
Polled is not a synonym for slow — it is a different architecture
Polling the REST API directly does not rescue it either. Demio caps accounts at 180 requests a minute and 5,000 calls a day[4], and a single ninety-minute webinar polled every five seconds would consume well over a thousand of those calls on its own. A design that spends a fifth of the daily budget watching one session is not a design.
Can you tell when somebody leaves my Demio session?
Only afterwards. The participants report you pull against a finished session carries a “left early” status, and that is the whole of it — a row in a report, not an event. So mid-session exit is a plain no on this platform, which is also what it is on every other row of the matrix, Zoom included.
| What happens | What Demio gives us |
|---|---|
| A text when somebody registers | A polled Zapier trigger, not a pushed event. It works; the timer is not ours. |
| A call before the session, and a text carrying the join link | Nothing needed. This runs off your session time and our own timer. |
| We stop contacting somebody already watching | A polled “Joins Webinar” trigger, with the same caveat as registration. |
| A call to somebody who walked out mid-session | Nothing during the session. A “left early” status appears in the report afterwards. |
| Working the people who did not show, after the event | The participants report, with attended, did not attend, completed, left early and banned. |
| A phone number to work with at all | A predefined phone field on the registration form. |
Two of those five are the ones that decide your show-up rate, and neither of them needs an event from Demio at all — including the call that gets the registrant to state in their own words when they will join. That micro-commitment is the mechanism we sell rather than any particular channel, which is the reason a platform with no webhooks is still perfectly workable for the job people actually hire us for.
Demio publishes attendance data. Can I plan against it?
One slice of it, carefully. Banzai and Demio’s 2024 report, drawn from more than 800,000 webinars hosted on Demio during 2023[5], breaks live attendance down by company revenue — and the under-$1M band comes out at 22%. That band is solo operators and small information businesses, which is the closest published cohort to the people who read this site, and 22% sits inside the convergent 21–36% range we use as a planning assumption for a show-up rate.
Treat any single-year platform figure as unreliable
A planning assumption is not a promise, ours or Demio’s. Where every widely-quoted webinar benchmark comes from, and which population each one actually measures, is set out on show-up rate by traffic source.
What should I check in my own Demio account?
Three things, all answerable from your own settings in an afternoon and none of them requiring a conversation with us.
Confirm the phone field is on the registration form
Demio supports a predefined phone field, but a form without it produces registrants we cannot text or call, and no amount of integration work fixes that afterwards. What the form says beside the field — who is being consented to, and whether an artificial voice is mentioned — is a separate and more important question.
Find who holds the API credential
The key and secret live in account settings rather than being issued on request, so this is a permissions question inside your own team rather than an application to a vendor. Note the daily call ceiling while you are in there: 5,000 for a paying account, 100 on a free trial.
Decide what the post-session report is for
It carries attended, did not attend, completed, left early and banned. That is enough to work the people who did not show and the people who left before the end — as a follow-up after the event, which is what it is, rather than a rescue during it.
If you are choosing a platform rather than describing one, nothing here is an argument to move. The two capabilities that carry the sequence are present, and the missing one is the capability we decline to sell on every platform in the table.
Frequently asked questions
Not in its official API. Registration reaches an outside system through Zapier's “New Webinar Registration” trigger, which is not marked instant and therefore polls. It works, and the interval belongs to the integration platform rather than to Demio or to us.
We could not corroborate one. Third-party integration guides describing Demio webhook endpoints contradict the platform's own published API surface and its own help centre, and we would rather record “no webhooks documented” than build against a claim the vendor does not make. If Demio ships webhooks, this page changes and the date under our matrix changes with it.
Not during the session. The only leave signal on the platform is a “left early” status in the participants report pulled after the session ends. They get picked up afterwards along with everyone else who did not stay — as a follow-up, not a rescue. That capability is a no on every platform in our matrix, Zoom included.
No. It has a phone field on the registration form and a workable route for registration and join events, and the part of the sequence with the strongest evidence behind it — the call before the session — needs no platform events at all. What it costs you is the ability to react to things inside the session in the same minute they happen.
Use the cohort, not the headline. The under-$1M revenue band came out at 22% across more than 800,000 webinars, which sits inside the 21–36% range we treat as a planning assumption. The platform's own headline figure moved from 52% to 38% to 35% across three consecutive annual reports, so a single-year headline is not something to build a forecast on.
You run a webinar. We come in and increase your show-up rate and your post-webinar sales, with our AI voice and SMS system — and you finally know why every registrant signed up. The whole table, with the date it was last checked, is on platforms. If you are weighing Demio against another automated-session platform, StealthSeminar does push its events, and WebinarJam pushes registration and arrival too, at the cost of an approval queue in front of the API. The way we ask to be measured is the pilot, and if that is worth twenty minutes, book a call.
Founder & Operator, CallHush
Founder and operator of CallHush. The offer is one sentence: you run a webinar, and we increase your show-up rate and your post-webinar sales with an AI voice and SMS system. CallHush has no closed clients yet — the first engagement is a pilot run as a split of the client’s own registrant list, and nothing on this site is presented as a client result.
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