# Sider AI Alternatives 2027: 11 Paid, Free & Open-Source

Source: https://zekaiwork.com/alternatives/sider-ai/
Prices checked: 2026-11-11 (Zekai Price Ledger)

The best Sider AI alternatives in 2027 are Monica (best overall, $8.3/mo), MaxAI (best free plan: 3 Pro chats per day) and NextAI Translator (best open source, AGPL-3.0). Sider AI itself starts at $10/mo. Zekai checked these prices on vendor pages on 11 Nov 2026; 8 more are compared below, including 4 with a free plan and 2 open source.

| Tool | Type | Starting price | Free plan limit | Licence | Best for | Price checked | Links |
|---|---|---|---|---|---|---|---|
| Sider AI (the tool being replaced) | — | $10/mo | No | — | — | 2026-11-11 | [pricing](https://sider.ai/pricing) |
| Monica | Free plan + paid | $8.3/mo | 40 basic-model accesses daily | — | Multi-model sidebar plus agents | 2026-11-11 | [site](https://monica.im) [pricing](https://monica.im/pricing) [Zekai page](https://zekaiwork.com/ai-tools/monica/) |
| MaxAI | Free plan + paid | $12/mo | 3 Pro chats per day, unlimited free chat | — | Team-ready sidebar with a free tier | 2026-11-11 | [site](https://www.maxai.co) [pricing](https://www.maxai.co/pricing/) [Zekai page](https://zekaiwork.com/ai-tools/maxai/) |
| Merlin | Paid | Not checked | No free plan | — | AI sidebar with 70+ tools | 2026-11-11 | [site](https://www.getmerlin.in) |
| HARPA AI | Paid | Not checked | No free plan | — | Browser automation with your own API keys | 2026-11-11 | [site](https://harpa.ai) [Zekai page](https://zekaiwork.com/ai-tools/harpa-ai/) |
| Claude | Free plan + paid | $17/mo | Limited usage every 5 hours and every week | — | Assistant with Claude in Chrome | 2026-11-11 | [site](https://claude.ai) [pricing](https://claude.com/pricing) [Zekai page](https://zekaiwork.com/ai-tools/claude/) |
| Gemini | Free plan + paid | $4.99/mo | Free with a Google Account; usage limits apply | — | Cheapest paid tier, Google-integrated | 2026-11-11 | [site](https://gemini.google) [pricing](https://gemini.google/us/subscriptions/?hl=en) [Zekai page](https://zekaiwork.com/ai-tools/gemini/) |
| Microsoft Copilot | Free plan + paid | $19.99/mo | Free tier with lower usage than paid Microsoft 365 plans | — | Copilot tied to Microsoft 365 apps | 2026-11-11 | [site](https://copilot.microsoft.com) [pricing](https://www.microsoft.com/en-us/copilot/solutions/individuals) [Zekai page](https://zekaiwork.com/ai-tools/microsoft-copilot/) |
| ChatGPT | Free plan + paid | $20/mo | Unlimited text chats with GPT-6; other features limited | — | Single-vendor assistant used in its own app | 2026-11-11 | [site](https://chatgpt.com) [pricing](https://chatgpt.com/pricing) [Zekai page](https://zekaiwork.com/ai-tools/chatgpt/) |
| NextAI Translator | Open source | Free (self-hosted) | No limit (self-hosted) | AGPL-3.0 | Open-source in-page translation browser extension |  | [code](https://github.com/nextai-translator/nextai-translator) [Zekai page](https://zekaiwork.com/free-open-source/nextai-translator/) |
| LibreChat | Open source | Free (self-hosted) | No limit (self-hosted) | MIT | Self-hosted chat across many providers |  | [code](https://github.com/LibreChat-AI/LibreChat) [Zekai page](https://zekaiwork.com/free-open-source/librechat/) |
| Chatbox | Open source | Free (self-hosted) | No limit (self-hosted) | GPL-3.0 | Desktop AI client for local models |  | [code](https://github.com/chatboxai/chatbox) [Zekai page](https://zekaiwork.com/free-open-source/chatbox/) |

## How each alternative compares with Sider AI

- **Monica** (Free plan + paid, $8.3/mo, checked 2026-11-11): Monica's Pro plan is $8.3 a month billed yearly for 5,000 basic and 200 advanced model queries a month, with Deep Research and slides agents, compared with Sider's credit tiers. Switch if you want a lower annual price and a fixed monthly query count instead of Sider's credit pools. Stay with Sider AI if you want Sider's browser-driving Hand agent and the dedicated cloud computer on higher tiers.
- **MaxAI** (Free plan + paid, $12/mo, checked 2026-11-11): MaxAI's pricing page shows Free with unlimited chat on a fast model and 3 Pro chats daily, and Pro at $12 per member monthly on yearly billing with team management. Switch if you need per-member team billing and a free plan with unlimited chat on a fast model. Stay with Sider AI if you want Sider's cloud-computer browser agent and its image, video and slide creation under one plan.
- **Merlin** (Paid, Not checked): Merlin's pricing page lists Pro at $19 a month billed yearly ($228) with unlimited access to basic models and 70+ AI tools, and a Teams plan at $15 per seat. Switch if you want unlimited basic-model use and a long list of single-purpose AI tools in the extension. Stay with Sider AI if you want Sider's Hand agent that carries out tasks across real websites for you.
- **HARPA AI** (Paid, Not checked): HARPA sells a one-time lifetime X plan at $240 where you bring your own API keys or web sessions, alongside S1 at $12 a month billed annually with a yearly token balance. Switch if you prefer a lifetime licence and want to connect your own ChatGPT, Claude or Gemini accounts. Stay with Sider AI if you want credits-based plans that include image and video generation without supplying keys.
- **Claude** (Free plan + paid, $17/mo, checked 2026-11-11): Claude's Pro plan, $17 a month on annual billing, includes Claude in Chrome and Microsoft 365 integration, but it only runs Anthropic models rather than several vendors' models. Switch if you accept a single model family and want its Chrome extension included with chat and Projects. Stay with Sider AI if you want GPT, Gemini, DeepSeek and other vendors' models together in one sidebar.
- **Gemini** (Free plan + paid, $4.99/mo, checked 2026-11-11): Gemini's Google AI Plus is $4.99 a month with 2x the free usage limits, and AI Pro is $19.99; every plan is tied to a Google Account. Switch if you want the lowest paid entry price and your browsing already runs through a Google Account. Stay with Sider AI if you want a vendor-neutral sidebar offering several labs' models and a browser-automation agent.
- **Microsoft Copilot** (Free plan + paid, $19.99/mo, checked 2026-11-11): Microsoft's Premium plan at $19.99 a month bundles Copilot with Word, Excel, PowerPoint and Outlook desktop apps plus 1 TB of storage, rather than a browser sidebar alone. Switch if you want Copilot included with Office apps and cloud storage in one Microsoft subscription. Stay with Sider AI if you only need a browser sidebar and do not want a Microsoft 365 bundle.
- **ChatGPT** (Free plan + paid, $20/mo, checked 2026-11-11): ChatGPT's Go plan is $6 a month and Plus $20; both run OpenAI models in the ChatGPT app rather than a sidebar placed over any web page. Switch if you want OpenAI's models only, with an inexpensive $6 Go tier available. Stay with Sider AI if you want an assistant that sits beside whatever page is open and summarises it in place.
- **NextAI Translator** (Open source, Free (self-hosted)): NextAI Translator is a cross-platform desktop app and browser extension for ChatGPT-powered translation, covering one of Sider's functions rather than its full chat and agent set. Switch if translating selected text is your main use and you want AGPL-3.0 code running with your own key. Stay with Sider AI if you need summaries, chat with PDFs and an agent, not translation alone.
- **LibreChat** (Open source, Free (self-hosted)): LibreChat is a self-hosted chat site connecting several providers with agents and MCP, but it is a web app you open, not an extension on top of the page. Switch if you want to host your own multi-model chat and control stored conversations. Stay with Sider AI if you want an in-browser sidebar that reads the page you are on without hosting anything.
- **Chatbox** (Open source, Free (self-hosted)): Chatbox is a GPL-3.0 desktop client for multiple model providers and local models; it works as a separate window instead of a page-aware browser sidebar. Switch if you want a free desktop client with your own keys or local models. Stay with Sider AI if you want the assistant inside the browser reading the open tab.

## Open-source options in detail

- **NextAI Translator** (https://github.com/nextai-translator/nextai-translator): Licence: AGPL-3.0
- **LibreChat** (https://github.com/LibreChat-AI/LibreChat): Licence: MIT
- **Chatbox** (https://github.com/chatboxai/chatbox): Licence: GPL-3.0

## Questions

### What is the best alternative to Sider AI in 2027?
Monica is the best overall Sider AI alternative on this page ($8.3/mo). For no cost, MaxAI has a free plan (3 Pro chats per day, unlimited free chat). To self-host, NextAI Translator is open source (AGPL-3.0).

### Is there a free version of Sider AI?
No. Sider AI has no free plan; paid plans start at $10/mo, checked on 11 Nov 2026.

### Is there a 100% free alternative to Sider AI?
Yes. NextAI Translator, LibreChat, Chatbox are open source and free to self-host. Monica, MaxAI, Claude, Gemini, Microsoft Copilot, ChatGPT have a free plan with limits, shown in the table.

### What is cheaper than Sider AI?
Gemini starts at $4.99/mo, against $10/mo for Sider AI, as listed on each vendor's pricing page on 11 Nov 2026.

### How much do Sider AI alternatives cost for a team of 5?
If each of 5 people buys the entry paid plan, at the prices Zekai checked on 11 Nov 2026, the monthly cost is Gemini $24.95/mo, Monica $41.50/mo, MaxAI $60/mo, against Sider AI $50/mo for Sider AI. Team and business plans can cost more per seat. The Zekai Cost Finder on this page recalculates for any team size.

### Which is better, Monica or Sider AI?
Monica's Pro plan is $8.3 a month billed yearly for 5,000 basic and 200 advanced model queries a month, with Deep Research and slides agents, compared with Sider's credit tiers. Choose Monica if you want a lower annual price and a fixed monthly query count instead of Sider's credit pools. Stay with Sider AI if you want Sider's browser-driving Hand agent and the dedicated cloud computer on higher tiers.

### What is better than Sider?
Monica is the nearest like-for-like extension, MaxAI suits teams, and Claude or Gemini fit if you want a single vendor's own browser assistant.

## Related on Zekai

- [Monica alternatives](https://zekaiwork.com/alternatives/monica/)
- [Claude alternatives](https://zekaiwork.com/alternatives/claude/)
- [Gemini alternatives](https://zekaiwork.com/alternatives/gemini/)
- [Microsoft Copilot alternatives](https://zekaiwork.com/alternatives/microsoft-copilot/)
- [ChatGPT alternatives](https://zekaiwork.com/alternatives/chatgpt/)
- [AI for Personal Productivity & Executive Assistants](https://zekaiwork.com/professions/ai-personal-productivity-executive-assistants/)

---
Live table, team cost finder and price alerts: https://zekaiwork.com/alternatives/sider-ai/