BigMarker vs ON24: Room Size, AI Content and Who Owns It

The short answer: if one launch webinar will pull more than 5,000 people into the room at once, or the same programme also runs badge printing and check-in for an in-person conference, BigMarker is the simpler contract: every Webcast plan is listed as configurable up to 1M live attendees, and its event packages cover check-in, badges and a mobile app (BigMarker pricing). ON24 caps live Classic Elite events at 5,000 concurrent attendees unless a Large Event Request is approved, and Next Generation Elite at 2,000 (ON24 large event article). ON24 wins when the webinar is raw material for a content library: its AI turns each session into blog posts, ebooks, FAQs and clips for nurture pages (ON24 AI content article). Both quote prices only on request, on pages read on 26 October 2026, and ON24 now belongs to Cvent (Cvent release).

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Put three numbers on one page before either demo:

1. What last year's attendee cost you. For example, if the current platform cost €24,000 for the year and 3,200 people attended live, each attendee cost €24,000 / 3,200 = €7.50. Neither vendor publishes a price (BigMarker pricing), so give both the same figure and ask them to quote against it.
2. The systems already in the building. Name your CRM and your events tool. BigMarker's pricing FAQ lists Salesforce, HubSpot, Marketo, Eloqua, Pardot and Microsoft Dynamics, plus Zapier and webhooks (pricing); ON24 sends HubSpot data through its own app and runs a REST API (HubSpot integration, REST API overview). If the events team already books venues in Cvent, ON24 now shares its owner.
3. The hour sales wants the list. ON24 documents that live attendance reaches HubSpot 30 minutes to 2 hours after the event ends, and on-demand viewing 4 to 12 hours later (HubSpot integration). Ask BigMarker for its timing in writing, then judge both against the follow-up you plan.

Terms worth getting in writing

Where they differ

Who you are signing with

Cvent closed its purchase of ON24 on 1 April 2026 and says it will keep investing in the ON24 platform, with a focus on AI and enterprise reliability, as part of one connected platform for in-person, hybrid, virtual and webinar formats (Cvent release). The product keeps selling under its own name. For a buyer, the roadmap now answers to a parent that also sells its own webinar and event products. Ask which company signs your contract, and what the renewal terms say about price.

Content after the session

ON24 builds a content library from every session. Once a live event is archived, it can generate a blog post, an ebook, an FAQ, key takeaways, a follow-up email, social posts, a podcast and key-moment clips, each downloadable as an editable Word file or media file (using AI content). BigMarker's Content Studio works from a processed recording: AI chapters, a one-minute teaser and a five-minute summary by default, 9:16 social videos and written pieces from your own prompt, and it is in preview for Enterprise accounts (Content Studio guide). A team that measures webinars by the content they feed for six months leans to ON24. A team that measures by the event leans the other way.

What the quotes will cover

There are no figures to compare on 26 October 2026. BigMarker's pricing page shows "Request pricing" on all three Webcast plans and on its registration, event, media hub and eLearning licences, with events priced per event and eLearning per platform per year. ON24 publishes no prices on any page that loaded that day, and its own site blocked most automated reading, so the ON24 homepage is the only place to start. Ask each for a quote covering the same hosts, the same peak audience, the same CRM and the same AI content, for the same term.

How big one room gets, and who pays to grow it

ON24 caps its Classic live events at 5,000 concurrent attendees by default; a Large Event Request needs at least two weeks' notice, four in peak hours, and a Large Event Reservation Fee is billed on the capacity requested; the request does not move the attendee number above which your contract's overage fee starts (large event article). The default you accept at signing becomes the line above which the next fee is charged, which suits ON24's revenue better than a buyer planning one big launch a year. BigMarker states the opposite ceiling, configurable up to 1M live attendees on every Webcast plan (pricing); get the configured number written into the order form all the same.

One agent step: a webinar turned into drafts, then edited

On ON24, switch on "Generate a collection of AI-generated content" under Smart Plays on the event's Overview page, with the event set to one of the supported languages, Dutch, German, French and Spanish among them; the drafts land in the Media Manager up to four hours after the archive is ready, and the event creator gets an email (AI content article). The human check is the edit: download each draft as Word, play the recording beside it, and strike any claim, figure or customer name the presenter did not say, before anything goes to a nurture page. ON24 notes that the content runs on Microsoft Azure OpenAI and that you own the output. In BigMarker's Content Studio, the equivalent check is the "Read AI Response" button, which shows how the model built a custom piece (Content Studio guide).

Which job each one wins

Choose BigMarker if your job is one programme across formats: webinars, an in-person conference with badges and check-in, and certification courses, under one registration system, with launch audiences that will not fit in 5,000 seats.

Choose ON24 if your job is feeding a year of nurture content from your webinars, with AI drafts in the event's language, and the company already runs its in-person events on Cvent.

If the real question is how many event and webinar tools the company should pay for, now that one owner sells ON24 next to its own event products, that is a stack question rather than a vendor one. A one-week review like the Startup Fixer, which I sell, maps it before a multi-year contract does. Background on BigMarker is in its glossary entry and in how to score webinar leads with BigMarker.

FAQ

Is ON24 still sold after the Cvent deal?

Yes. Cvent's release of 1 April 2026 says it plans to keep investing in and growing the ON24 platform, and the ON24 homepage still offered demos when it loaded on 26 October 2026 (Cvent release).

What happens above 5,000 live viewers on ON24?

On Classic live events you file a Large Event Request, ideally two weeks ahead and four in peak hours, and pay a reservation fee on approval; Next Generation Elite stays at 2,000 concurrent (large event article).

Does BigMarker translate a live session?

Yes, as a paid add-on: presenters speak their own language and attendees pick theirs, with captions and translated audio, on webcast webinars (AI translation guide).