Monica and Sider alternative: in-browser AI with your own key
Monica and Sider are two of the most popular AI sidebars for Chrome. Here's what each one includes, what it costs and when using AI with your own key works out better.
Monica and Sider put an AI chat next to any page: you ask about what you're reading, get a summary or some help writing. Both run on a subscription that bundles access to several AI models, such as GPT, Claude or Gemini.
NexoPad takes a different route: you connect your own key from an AI provider and use it on the text you select, in the side panel or from the right-click menu. You choose the model and pay the provider directly, or nothing at all if you pick one with a free tier. Here are the differences so you can choose with confidence.
What Monica and Sider are
Monica
An all-in-one AI assistant: chat with several models, summaries of pages and YouTube videos, PDF chat, translation, image and video generation, and agents. It has an extension for Chrome and Edge, plus desktop and mobile apps.
Sider
An AI sidebar for chatting about the page you're reading, translating pages, PDFs and images, and creating images, videos and slides. Its current paid plans include an agent that does tasks on websites for you and a cloud computer.
NexoPad
A productivity extension with built-in AI: fix, rewrite, summarize or translate the text you select, and chat in the side panel. It runs on your own key and adds text shortcuts, notes and links.
Comparison table
| Monica | Sider | NexoPad | |
|---|---|---|---|
| How you access AI | Models included in your plan | Models included in your plan | Your own key from 10 providers |
| Use your own key | We couldn't find it on their website | Yes, with some providers; some features only work in its own mode | Yes, always |
| Free plan | 40 basic-model queries per day | 30 basic credits per day, per its help center | 15 AI uses to try it out |
| Paid price (yearly) | From $8.30/month ($99/year) | From $8.33/month ($100/year) | Pro: $49/year, plus what you spend with your provider |
| AI on selected text | Yes | Yes | Yes, with quick actions and your own instruction |
| PDFs, images, video and YouTube | Yes | Yes | No |
| Agents that browse for you | Yes | Yes | No |
| Text templates with shortcuts | No (prompt library, yes) | No (prompt library, yes) | Yes, with variables |
| Browsers | Chrome and Edge, plus apps | Chrome and Edge, plus apps | Chrome, Edge, Firefox, Opera and Brave |
What using your own key means
With Monica or Sider you pay a fee and they give you access to the models, with a monthly limit on queries or credits. With your own key (often called *BYOK*, "bring your own key") it works the other way around: you create a key with the AI provider you like, paste it into NexoPad, and every request goes straight from your browser to that provider. The key stays stored in your browser.
The upside is that you choose the model and only pay for what you use. And five of the providers NexoPad supports (Groq, Mistral, Cohere, OpenRouter and Google Gemini) have a free tier: you just sign up, within each provider's usage limits. We show you how in our guide to getting a free AI API key.
NexoPad's AI, in detail
- On the text you select: a small button appears and you pick Fix, Formal, Soften, Shorten, Summarize or Translate, or type your own instruction. If you're in a text field, you apply the result right there.
- In the right-click menu: the same actions plus translation into eight languages, without opening anything else.
- In the side panel: a Tool mode to process text (including summarizing the page you have open) and a Chat mode to talk with the AI.
- 10 providers: OpenAI, Anthropic, Google Gemini, DeepSeek, Groq, xAI, Mistral, Cohere, OpenRouter and Together. You can save several keys and switch between them.
- All in one place: save an answer as a note and keep it next to your text shortcuts and links.
When to choose each
Choose Monica if…
You want a single subscription with lots of models and tools: PDF chat, YouTube summaries, images, video and agents, on mobile and desktop too.
Choose Sider if…
You read and translate a lot of content (pages, PDFs and images) or want an agent that does tasks on websites for you. You can use your own key for some of its features.
Choose NexoPad if…
Most of your day is writing and replying: you want AI on your own text, with your key and the model you choose, plus text shortcuts, notes and links in the same extension.
How to get started with NexoPad
Get a key
Sign up with a provider that has a free tier, such as Groq or Google Gemini, or use a key from a provider you already pay for.
Paste it in the AI tab
Open the NexoPad side panel, go to the AI tab, choose the provider and paste your key. The details are in the AI providers guide.
Select some text and try it
Highlight a paragraph on any website and click the AI button that appears next to it. For more ideas, see our list of AI extensions for Chrome.
FAQ
Are Monica and Sider free?
Both have a free plan with limited daily use: 40 basic-model queries on Monica and 30 basic credits on Sider, according to their websites as of October 14, 2026. For more use or advanced models you need a paid plan.
Do I pay for the AI separately with NexoPad?
You pay your AI provider for what you use, or nothing if you choose one with a free tier and stay within its limits. NexoPad's free plan includes 15 AI uses so you can try it; with Pro ($49/year) it's unlimited.
Can NexoPad summarize PDFs or YouTube videos like Monica or Sider?
No. NexoPad works with text: the text you select, the text you paste into the side panel or the page you have open. If you need PDFs, video or images, Monica or Sider are a better fit.
Where is my key stored?
In your browser. Requests go straight from your browser to the provider you choose, without passing through NexoPad's servers. Even so, don't paste passwords or sensitive data into any AI.
Published on October 14, 20267 min read
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