Slido free plan limits for a 300-person conference, and cheaper options
Updated: · Alex Ryk, founder of AnyEventTool
Short answer
Slido's free Basic plan allows up to 100 participants and 3 polls per slido, so a 300-person conference needs a paid plan: the cheapest covering 300 is one-time Professional at 240 EUR for 7 days. Cheaper routes: Vevox one-time 195 USD, AhaSlides Pro 24.95 USD for one month, Mentimeter Free's once-a-month unlimited session, or AET's free live quiz (no published player cap). Checked 15 October 2026.
Key facts
- Slido Basic (free): up to 100 participants, basic audience Q&A and 3 polls per slido; the cap counts every device that joins over the whole meeting (checked 15 October 2026)
- Slido plans that cover 300: one-time Professional 240 EUR per event (up to 1,000 participants, 7 days); annual Professional 60 EUR/month, billed 720 EUR a year; Engage (200) is too small
- Slido sells only one-time (7-day) and annual plans; its FAQ says monthly payments are not accepted
- Mentimeter Free: 50 participants a month plus unlimited participants once a month; Basic 11.99 USD per presenter/month billed yearly removes the cap
- Other ways to cover 300: Vevox One Time Standard 195 USD for 7 days (1,500), AhaSlides Pro 24.95 USD for one month (2,500), Crowdpurr Seminar 149.99 USD for one month (500), Kahoot! 360 Event Plus 299 EUR for 30 days (1,000)
- Free caps elsewhere: Vevox 100 per session, AhaSlides 50, Poll Everywhere 40 (700 for 30 days), Crowdpurr 20, Kahoot! 360 Express 15
- AET: live quiz on the Free plan with no separate player cap published; multiple choice only, no Q&A, polls or word clouds
- Disclosure: written by the AnyEventTool team; AET is included with its limitations
| # | Tool | Best for | Pricing |
|---|---|---|---|
| 1 | Slido | Moderated Q&A and polls during talks | Free: 100 participants, 3 polls per slido; one-time Professional 240 EUR (1,000, 7 days); annual from 15 EUR/month |
| 2 | Vevox | Cheapest one-time plan for a 300-person hall | Free: 100 per session; One Time Standard 195 USD (1,500, 7 days) |
| 3 | Mentimeter | One big presentation a month on a free plan | Free: 50 participants a month plus unlimited once a month; Basic 11.99 USD per presenter/month billed yearly |
| 4 | AhaSlides | Short paid month for a single event | Free: 50; Pro 24.95 USD/month (2,500) or 7.95 USD/month billed yearly |
| 5 | AnyEventTool (AET) | A quiz that lives on your event page | Included in Free (0 USD); AI quiz uses 1 of 10 monthly AI generations; Pro 29 USD/month (290 USD/year) |
Slido
Pros
- Strong audience Q&A
- One-time plans refundable before the event
- Annual plans do not auto-renew
Cons
- 3 polls on Free
- No monthly billing
- Free cap counts every device over the meeting
Vevox
Pros
- Unlimited basic polls, quizzes and Q&A on Free
- 1,500 participants for 195 USD
Cons
- Word clouds start on Starter
- Speed-scored quizzes on Pro
Mentimeter
Pros
- Once-a-month unlimited session
- Never blocks joiners mid-presentation
Cons
- Monthly cap on Free
- Per-presenter pricing
AhaSlides
Pros
- Monthly billing
- 2,500 participants on Pro
Cons
- 5 quiz and 3 poll questions per presentation on Free
- Joiners past the cap are refused
AnyEventTool (AET)
Pros
- No separate player cap published
- AI questions from your files, links or YouTube subtitles
- No accounts for players or speaker
Cons
- Multiple choice only
- No Q&A, polls or word clouds
What does Slido's free plan include?
Slido's free plan is called Basic. On slido.com/pricing (checked 15 October 2026) it includes:
- up to 100 participants per slido;
- basic audience Q&A;
- 3 polls per slido. Unlimited polls and quizzes start on the paid Engage plan.
How Slido counts: the limit is the total number of participants (devices) that join over the course of your meeting, not the number online at one moment. An audience of 300 that comes and goes during the day still counts as 300.
Paid plans come in two forms: one-time plans for a single event lasting up to 7 days, and annual plans. Slido's FAQ says monthly payments are not accepted. Prices exclude VAT.
What happens if 300 people join a free slido?
Slido's pricing page does not say exactly what happens past the cap. In Slido's own community forum, a Slido employee wrote on 13 June 2024 that the limit is not a hard cutoff for a few extra participants, and that at around 10% over the limit the host is warned and asked to upgrade. A later Slido Customer Care reply (11 April 2025) mentions sessions being blocked when the limit is reached (community.slido.com). 300 people is three times the free cap, so plan for a paid plan, not for tolerance.
Other vendors publish their rules on the pricing page:
- Mentimeter never stops people joining an ongoing presentation. You get an 8-hour grace period, then cannot start new presentations until the monthly limit resets.
- AhaSlides lets the presentation continue, but participants past the limit cannot join.
Sources: mentimeter.com/plans, ahaslides.com/pricing (checked 15 October 2026).
What does a 300-person conference cost on Slido and the alternatives?
One event, about 300 people, polls or a quiz during the talks. The cheapest published option on each tool that covers 300:
| Tool | Free plan participant cap | Price for a 300-person event | Notes |
|---|---|---|---|
| Slido | 100 per slido; 3 polls | One-time Professional: 240 EUR per event (up to 1,000, 7 days) | Annual Professional 60 EUR/month, billed 720 EUR a year, from 2 users; no monthly billing |
| Vevox | 100 per session; unlimited basic polls, quizzes and Q&A | One Time Standard: 195 USD for 7 days (up to 1,500) | Starter covers 250; Pro covers 1,500 at 24.95 USD/month on annual billing |
| Mentimeter | 50 a month, plus unlimited participants once a month | 0 USD if this is your one unlimited session that month; otherwise Basic 11.99 USD per presenter/month, billed yearly | Shown as 14 EUR in Europe; never blocks joiners mid-presentation |
| AhaSlides | 50; 5 quiz and 3 poll questions per presentation | Pro: 24.95 USD for one month (up to 2,500) | 7.95 USD/month if billed yearly; Essential (100) is too small |
| Poll Everywhere | 40 (700 for 30 days) | Present: 120 USD a year (700), annual billing only | For a one-time event its FAQ says to contact sales |
| Kahoot! 360 | 15 on the free 360 Express, 15-minute sessions | Event Plus: 299 EUR for 30 days (up to 1,000) | Commercial rights for external events are listed only on Event Ultra (799 EUR) |
| Crowdpurr | 20; 15 questions per experience | Seminar: 149.99 USD for one month (up to 500) | Built for trivia and audience games |
| AnyEventTool (AET) | Live quiz on Free; no separate player cap published | 0 USD | Quiz only: multiple choice, no Q&A, polls or word clouds |
Sources (checked 15 October 2026): slido.com/pricing, Kahoot! help: participant limits, kahoot.com: Kahoot!+ plans, kahoot360.com: event plans, mentimeter.com/plans, ahaslides.com/pricing, vevox.com: business pricing, vevox.com: one-time events, polleverywhere.com/plans, Wayground help: plans, Wayground for Business: participant limits, crowdpurr.com/pricing, Blooket help: is Blooket free?, Blooket: upgrade, anyeventtool.com/en/pricing. Prices are shown as each vendor shows them (with or without tax) and can vary by region and billing period.
Where is Slido the better choice?
- Audience Q&A. Slido is built around audience questions with voting; moderation of questions comes with Professional.
- Refundable one-time plans. Its FAQ says one-time plans can be cancelled or changed before the event for a refund.
- No surprise renewals. Annual plans do not renew automatically; Slido emails a reminder 30 days before they expire.
- Scale. One-time Premium covers 5,000 participants for 499 EUR; larger audiences on request.
If your 300-person conference mainly needs moderated Q&A for speakers, the one-time Professional plan is a sound buy. Source: slido.com/pricing (checked 15 October 2026).
Which cheaper option fits what you need?
| You need | Cheapest fit for about 300 people | Cost |
|---|---|---|
| Q&A and polls for one event | Vevox One Time Standard | 195 USD |
| Slides with polls and a quiz, one event a month | Mentimeter Free (once-a-month unlimited session) | 0 USD |
| Slides with polls and a quiz, several events in a month | AhaSlides Pro, one month | 24.95 USD |
| A quiz only, tied to your event page | AnyEventTool live quiz | 0 USD |
| Trivia night or game show | Crowdpurr Seminar, one month | 149.99 USD |
Read the small print that matters for your day: Mentimeter's unlimited allowance covers one session a month; Poll Everywhere's free plan shows 700 only for 30 days; AhaSlides Free stops at 5 quiz questions per presentation; Vevox lists speed-scored quizzes as a Pro feature. Sources as in the table above (checked 15 October 2026).
Where does AnyEventTool fit, and where does it not?
AnyEventTool (AET) is an event platform, not a Slido replacement. Its live quiz is a section of your event page: AI writes up to 40 multiple-choice questions per request from your materials (a file such as PDF, DOCX or PPTX, a web page, pasted text or a YouTube video with subtitles), players scan a QR code and type a nickname with no account, and the projector screen shows the leaderboard and podium. A separate speaker link lets a guest speaker host without an AET account.
Cost: the quiz is in the Free plan (0 USD, 3 new events a month). An AI quiz uses 1 of 10 monthly AI generations (Pro: 100, for 29 USD a month or 290 USD a year); quizzes you write yourself are unlimited. AET does not publish a separate player cap for the quiz; for 300 people, run a test game on the venue's Wi-Fi or mobile data first.
Limits: multiple choice only. No audience Q&A, polls, word clouds or open answers, so for speaker Q&A use Slido, Vevox or Mentimeter. Step by step: how to run a live quiz at an event; wider comparison: Kahoot alternatives for conferences and events.
Questions and answers
How many participants can join Slido for free?
Up to 100 per slido on the free Basic plan, with basic Q&A and 3 polls. Slido counts every device that joins over the course of the meeting (slido.com/pricing, checked 15 October 2026).
Can I run a 300-person conference on Slido's free plan?
Not reliably. 300 is three times the free cap. A Slido employee has written that a few extra participants are tolerated and that the host is warned at around 10% over the limit; a later Slido reply mentions blocked sessions. Budget for a paid plan.
What is the cheapest Slido plan for 300 participants?
The one-time Professional plan: 240 EUR excluding VAT for one event lasting up to 7 days, with up to 1,000 participants. Engage, at 60 EUR one-time, stops at 200.
Does Slido offer monthly billing?
No. Slido's FAQ says it sells one-time plans for events of up to 7 days and annual plans. Annual plans do not renew automatically.
Which free option comes closest to 300 people?
Mentimeter's free plan includes unlimited participants once a month, Poll Everywhere's free plan shows 700 for 30 days, and AnyEventTool's live quiz is free with no published player cap (quiz only). Slido and Vevox stop at 100 on their free plans.
Who wrote this comparison?
The AnyEventTool team. Competitor figures come from each vendor's own pricing or help pages, checked 15 October 2026. AET is included with its limits: no Q&A, polls or word clouds.
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