ReplyZen
- What it is
- AI comment reply and moderation tool
- How it bills
- Monthly AI replies and moderations
- Cheapest paid plan
- $29 Basic, billed monthly, VAT excluded; no yearly price shown
- Free option
- 14-day free trial: 500 AI replies, 500 moderations
ReplyZen alternative for Facebook comments
ReplyZen uses AI to write replies to comments, hide spam and send private messages on Facebook, Instagram and TikTok posts and ads. It is built for e-commerce brands, performance marketers and agencies. Plans are billed monthly by how many AI replies and moderations you use, and every plan includes unlimited Pages.
Prices and features checked
At a glance
Mentbot
- What it is
- Facebook comment automation
- How it bills
- By comments per day
- Cheapest paid plan
- $9 Basic, 100 comments a day
- Free option
- 14-day free trial
What you pay at your comment volume
Monthly price, billed monthly, for one Facebook Page. Mentbot includes every feature on every plan, so its price only changes with volume.
| Comments per day | ReplyZen | Mentbot |
|---|---|---|
| 100 | $149 Enterprise; about 3,000 replies a month, one AI reply per comment | $9 Basic plan, every feature |
| 1,000 | No listed price About 30,000 replies a month exceeds Ultra; custom price unpublished | $19 Pro plan, every feature |
| 3,000 | No listed price About 90,000 replies a month exceeds Ultra; custom price unpublished | $29 Premium plan, every feature |
Features for Facebook comments
Only what matters for answering comments on a Facebook Page.
| Feature | ReplyZen | Mentbot |
|---|---|---|
| Auto-reply to comments in public | Yes AI-written; publish automatically, above a confidence level, or after review | Yes |
| Auto-send a private Messenger message | Yes Automations send a Facebook private reply, alone or with a public reply | Yes |
| Keyword triggers | Limited AI checks plain-language conditions; no exact keyword matching documented | Yes |
| Limit rules to certain posts | Limited Every post, only ads, or only organic; no per-post choice documented | Yes Pick posts or use a hashtag |
| Auto-hide comments | Yes AI hides spam and abuse; custom rules in plain language | Yes |
| Auto-like comments | Yes AI likes only substantive comments; Facebook and TikTok | Yes |
| Alert when a customer is left waiting | Limited No alert feature found in the help centre; unclear | Yes Telegram alerts |
| Several Pages on the cheapest plan | Yes Unlimited agents and Pages on every plan | Yes Unlimited Pages |
| Visual chatbot flow builder | Limited Two-step DM with a button; no visual flow builder documented | No |
| Instagram, WhatsApp and other channels | Yes Instagram; TikTok in beta, without DM automation | No Facebook Pages only |
ReplyZen pricing
Monthly AI replies and moderations. 14-day free trial: 500 AI replies, 500 moderations.
| Plan | Monthly | What you get |
|---|---|---|
| Basic | $29 | 500 AI replies, 2,500 moderations a month |
| Pro | $69 | 1,500 AI replies, 7,500 moderations a month |
| Enterprise | $149 | 5,000 AI replies, 25,000 moderations a month |
| Ultra | $249 | 10,000 AI replies, 50,000 moderations a month |
| Custom | No listed price | Above Ultra's limits; contact sales |
Choose ReplyZen if
- You want AI to write each reply from your product info and website, not fixed wording.
- You run ads and want comments on them answered and spam hidden around the clock.
- You also manage Instagram and TikTok comments and want one place for all three.
- Your team wants to review AI drafts before they go live.
Choose Mentbot if
- You want replies in your own words, with several variants that rotate.
- You get hundreds of comments a day. Mentbot's Pro plan covers 1,000 a day for $19.
- You want rules on exact keywords or a hashtag, limited to specific posts.
- You want a Telegram alert when a customer message sits unread.
How to switch to Mentbot
- In ReplyZen, write down each automation: the public reply, the private message, and the situation that triggers it.
- Start a Mentbot free trial and connect your Facebook Pages. It takes about five minutes.
- Turn each ReplyZen trigger into keywords or a hashtag, and choose all posts or specific posts.
- Add your public reply variants and the private Messenger message, then turn on auto-hide or auto-like if you need them.
- Turn off ReplyZen for that Page so a comment doesn't get two replies, then test with a comment of your own.
Questions
How much does ReplyZen cost?
Plans start at $29 a month for up to 500 AI replies and 2,500 moderations (Basic). Pro is $69, Enterprise $149 and Ultra $249, all VAT excluded. Above Ultra's 10,000 AI replies a month you contact them for a custom plan. Prices checked on replyzen.ai on 14 September 2026.
Does ReplyZen send a private message to people who comment?
Yes. Its automations can reply publicly, send a private reply on Facebook, or both. You describe the trigger in plain language and AI decides if a comment matches, instead of matching exact keywords.
Is Mentbot cheaper than ReplyZen?
On price alone, yes. ReplyZen bills by AI replies a month, so 100 comments a day is about 3,000 replies and needs the $149 Enterprise plan. Mentbot covers 100 comments a day for $9 and 1,000 a day for $19. The difference is that ReplyZen writes each reply with AI, and Mentbot sends the replies you write.
Does Mentbot write replies with AI like ReplyZen?
No. Mentbot sends the public replies and private messages you write when a comment matches your keywords or hashtag. If you want AI to read each comment and answer from your product info, ReplyZen does that and Mentbot doesn't.
Does Mentbot work on Instagram or TikTok?
No. Mentbot works on Facebook Page comments only. ReplyZen also covers Instagram and TikTok, so it's the better fit if you need those channels.
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Sources
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