Side-by-side comparison · AI Browsers & Agents
Firefox vs Manus vs Opera One
Everything that matters when choosing between them, in one place: our rating, what each can do, what they cost, and the trade-offs.
Comparing 3 tools, the maximum.
At a glance
Pick it if: Business owners who want a trusted, independent browser and want to decide for themselves whether AI is on or off.
Pick it if: People who want to hand off whole tasks and don't want to build the automation themselves.
Pick it if: Anyone who wants a free Chrome alternative with a capable AI sidebar, tab organisation and a built-in VPN, without paying for anything.
Overview
| Attribute | Firefox | Manus | Opera One |
|---|---|---|---|
| In one line | Mozilla's free browser with optional AI you can switch off with one setting. | A general-purpose agent that takes a goal and works through it in its own browser. | Opera's free everyday browser with a built-in AI sidebar that reads your tabs. |
| Pricing model | Free | Freemium | Free |
| Starting price | Free | From $20/mo | Free |
| Free plan | Yes | Yes | Yes |
| Works with Claude Code | No | Yes | No |
Rating breakdown
Our scores out of 5. The higher bar in each row is highlighted.
| Attribute | Firefox | Manus | Opera One |
|---|---|---|---|
| Overall rating | 3.6 | 3.7 | 3.9Winner |
| Ease of useHow quickly someone non-technical gets value from it. | 3.5 | 4.5 | 4.5 |
| FeaturesHow completely it covers its own job, and how well the pieces fit together. | 3.0 | 4.0 | 3.0 |
| Output qualityHow good the results are before you fix them. | 3.5 | 3.5 | 3.5 |
| Value for moneyWhat you get for the price, including the free plan. | 4.5 | 3.0 | 4.5 |
| Speed & reliabilityHow fast it is and how often it falls over. | 3.5 | 3.5 | 4.0 |
Feature comparison
A tick means it does this today. A dash means we haven't checked.
| Attribute | Firefox | Manus | Opera One |
|---|---|---|---|
| Access & platform | |||
| Free plan | Yes | Yes | Yes |
| Mobile app | Yes | Yes | Yes |
| Desktop app | Yes | Yes | Yes |
| Browser extension | No | Yes | No |
| API access | No | Yes | No |
| Teams & business | |||
| Team workspace | No | Yes | No |
| Enterprise plan or SSO | Yes | Yes | No |
| Connects to other apps | Yes | Yes | Yes |
| Open source or self-hosted | No | No | No |
| AI abilities | |||
| Works with your files | No | Yes | Yes |
| Understands images | No | Yes | Yes |
| Makes images | No | Yes | Yes |
| Makes video | No | Yes | No |
| Writes code | No | Yes | No |
| Runs agents or automations | No | Yes | No |
| Learns your brand or style | No | No | No |
| Works in many languages | Yes | Yes | Yes |
| Capabilities score | 6/ 17 | 15/ 17 | 8/ 17 |
Pricing
Plans as listed on each vendor's site when we last checked. Confirm before you buy.
| Attribute | Firefox | Manus | Opera One |
|---|---|---|---|
| Plans | FirefoxOur pick Free Everyone, with AI on or off as you choose. | Free Free Quick questions and seeing what it can do. | Free Free Everyone. There is no paid tier for the AI. |
Smart Window beta Free Heavy researchers in the US, Canada or France. | ProOur pick From $20/mo, less with yearly billing Anyone who wants to hand off real research and build jobs. | Free with an Opera accountOur pick Free Anyone who wants chat history across devices and more images. | |
Pro (higher tier) From $40/mo, less with yearly billing Heavier users and anyone publishing websites with it. | |||
Team From $20/seat/mo Teams that want shared credits and admin controls. | |||
Enterprise Custom Large organisations. | |||
| Which plan to pick | There's nothing to pay. Use the sidebar with whatever AI account you already have. If you're in the US, Canada or France, try Smart Window with a free Mozilla account. Everyone else can join the waitlist. | Try the Free plan for a week to get a feel for how many credits a real task uses, then move to the $20 Pro tier. Only go higher if you run out most months or you want it to publish websites for you. | It's all free. Sign in with a free Opera account if you want your chats saved and more images; otherwise just download it and click Ask AI. Opera sells a separate VPN Pro, but you don't need it for the AI. |
Key features
| Attribute | Firefox | Manus | Opera One |
|---|---|---|---|
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Pros and cons
| Attribute | Firefox | Manus | Opera One |
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Who each one is for
| Attribute | Firefox | Manus | Opera One |
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Questions people ask
Which is better, Firefox, Manus or Opera One?
Opera One scores highest overall in our ratings (Firefox 3.6/5, Manus 3.7/5 and Opera One 3.9/5). Firefox is best for Keeping AI out of the browser entirely and using your own ChatGPT or Claude in a sidebar. Manus is best for multi-step research with a report at the end and lead lists and data gathering. Opera One is best for summarising long pages and YouTube videos and comparing suppliers or products grouped in a Tab Island.
Which is cheaper, Firefox, Manus or Opera One?
Firefox: It's free and open source. Manus: There's a free plan, and paid plans start at From $20/mo. Opera One: It's free to use.
How we compare
Ratings are our own, from using each tool, across ease of use, features, output quality, value for money, speed & reliability.
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