AI Search Engine Comparison 2026: Perplexity, Google AI Mode, Deep Research, ChatGPT Atlas and More (Pricing & Free Plans)

When choosing an AI search engine, there are many factors to compare, such as pricing structures, the availability of a free plan, the accuracy of Japanese support, and supported platforms. Additionally, tools differ significantly in their strengths depending on features like autonomous research and browser integration, going beyond simple information retrieval.

This article compares 10 major tools, including Perplexity AI and Google AI Mode, based on data listed on AIpedia (as of November 2026). We outline each service's pricing, free plan, Japanese support, and platforms, along with specific strengths and weaknesses.

We also explain recommendations by goal, such as market research or development work, and key points on how to choose without making mistakes. Check the details you care about before implementation and find the AI search engine that fits your needs.

What Is an AI Search Engine? What It Can Do and What to Know Before Choosing

AI search engines go beyond simple keyword searches. They collect web information in real time and generate answers with sources. For example, Perplexity AI and Google AI Mode provide comprehensive answers that integrate multiple sources. Additionally, OpenAI Deep Research and Gemini Deep Research can autonomously browse the web to create detailed research reports.

• Sourced answer generation: Displays source URLs to make it easy to verify information reliability.
• Autonomous deep-dive research: For complex questions, AI automatically breaks down sub-queries and performs multi-stage analysis.
• Conversational follow-up: You can deepen or refine answers through dialogue rather than ending with a single search.
• Browser integration: Environments like ChatGPT Atlas or Perplexity Comet allow you to instantly summarize or ask questions about the page you are viewing.
• Privacy-focused search: Search without trackers or ads, similar to Kagi Search or Brave Search.
• Specialized domains: Provides answers specialized for developer technical questions with code examples, like Phind.

When choosing a tool, first check the free usage limits. For example, Perplexity AI and Brave Search offer basic features on their free plans. However, according to AIpedia data, OpenAI Deep Research is a feature available only in plans at or above ChatGPT Plus ($20/month). Also, conditions vary by service; for instance, Kagi Search’s free plan has a limit of 100 queries per month.

The level of Japanese support is also an important point. Many tools support Japanese, but some, like Perplexity Comet or Dia, may have partial support. Furthermore, since the UIs of Kagi Search and Brave Search are primarily in English, you may need to get used to operating them.

Consider your usage environment and target users as well. Options range from those that work entirely in a web browser to VSCode extensions (Phind) or native browsers (ChatGPT Atlas). Features like team sharing or API access may differ depending on whether you are an individual or a business user. We recommend checking the official website for the latest information.

Comparison of 10 Key Tools (Pricing, Japanese Support, Platforms)

Tool	AIpedia rating	Main plans	Japanese support	Platforms
Perplexity AI	4.3	free plan (basic search) / Pro $20/month (unlimited Pro Search, file uploads, API access) / Enterprise (contact sales)	Supported	Web, iOS, Android, Chrome extension
Google AI Mode	4.3	Free (integrated into Google Search) / Google AI Ultra ¥36,400/month for advanced features	Supported	Web, iOS, Android
OpenAI Deep Research	4.6	Plus $20/month (100 uses per month) / Pro $200/month (unlimited) / Team $25/user/month	Supported	Web, iOS, Android, macOS, and others
Gemini Deep Research	4.4	Included in Google One AI Premium $19.99/month / Workspace add-on (contact sales)	Supported	Web, iOS, Android
ChatGPT Atlas	4.6	Free (basic browser features) / Agent Mode requires ChatGPT Plus $20/month or higher / Parallel Agent execution requires Pro $200/month	Supported	macOS, Windows, iOS, Android
Perplexity Comet	4.4	Free (basic features) / Perplexity Pro $20/month for additional features	Partial support	macOS, Windows
Dia	4.2	Free (basic features) / Pro version planned	Partial support	macOS, Windows
Kagi Search	4.3	Free (100 uses per month) / Starter $5/month / Professional $10/month	Partial support (Japanese search available, UI in English)	Web, iOS, Android
Brave Search	4.1	Free (with ads) / Premium $3/month (ad-free) / Leo Premium $15/month	Partial support (Japanese search available, UI primarily in English)	Web, iOS, Android, desktop browser
Phind	4.2	free plan (10 uses per day, Phind model) / Pro $20/month (unlimited, GPT-4o/Claude available) / Team $30/user/month	Partial support	Web, VSCode extension

Ratings are out of 5 points by the AIpedia editorial team. Pricing and plans may change. Please check the official website of each tool for the latest information before signing up.

Features, Pricing, and Best For: 10 Tools

1. Perplexity AI

Perplexity AI is an AI search engine that searches the web in real time and generates answers with sources. It collects and integrates data from multiple information sources to present comprehensive answers in natural language. It also features a Focus function to narrow the search scope to Web, academic, video, or social media.

• Strengths: Every answer includes numbered source URLs, allowing you to immediately verify the accuracy of the information.
• Strengths: The Pro Search feature automatically breaks down questions to conduct deep-dive investigations and generate comprehensive reports.
• Strengths: It gathers information from diverse sources such as academic papers (via Semantic Scholar integration), news, and forums. You can organize research results by topic using the Spaces feature and share them with your team.
• Strengths: The Pro plan allows you to switch between multiple AI models like GPT-4o, Claude, and Gemini, and supports file uploads and PDF analysis.
• Things to note: The accuracy of collecting Japanese sources is lower compared to English, making it less suitable for researching purely Japanese information in some cases.
• Things to note: It falls short of ChatGPT or Claude for creative tasks such as writing long documents or interactive brainstorming. The free plan has limits on the number of Pro Search uses.

Pricing: Free plan (basic search) / Pro $20/month (unlimited Pro Search, file uploads, API access) / Enterprise (contact sales)

Best for: Individuals conducting academic research or business research where information sources are critical. It is suitable for business professionals and individual users who want to quickly obtain accurate information with sources.

See detailed features, pricing, and FAQ for Perplexity AI

2. Google AI Mode

Google AI Mode is an interactive AI search mode integrated into Google Search. In addition to traditional keyword searches, the AI understands the intent of your questions and provides answers in a conversational format by integrating multiple information sources. It operates by combining the reasoning capabilities of the Gemini model with Google's web index.

• Strengths: Since it is integrated into Google Search, no additional app installation or account registration is required. You can start using it immediately with your existing Google account, and it integrates with your search history.
• Strengths: Answers automatically include source links, making it easy to verify the basis of the information. It supports follow-up questions, allowing you to dig deeper into information through conversation.
• Things to note: Availability is expanding gradually, so whether you can use it may vary by region or account. Answers are subject to Google's policy constraints, and the depth of responses to specialized questions may be inferior to Perplexity. Verify the accuracy of AI-generated answers by opening the sources.

Pricing: Free (integrated into Google Search) / Google AI Ultra ¥36,400/month for advanced features

Best for: Individuals who use Google Search daily and want to try AI-powered interactive search without installing new apps. It is also recommended for business professionals and individual users who want to easily gather information in Japanese while checking answers with source links.

3. OpenAI Deep Research

OpenAI Deep Research is a tool that functions as an autonomous research agent. For complex questions, it automatically collects and analyzes information from the web. It generates comprehensive research reports with sources.

• Strengths: Automatically scans hundreds of web sources and generates detailed reports.
• Strengths: All information includes source links, making fact-checking easy.
• Things to note: Report generation may take 5 to 30 minutes.
• Things to note: According to AIpedia data, a plan of ChatGPT Plus ($20/month) or higher is required. The scope of availability may change, so please check the official website. It may not be able to retrieve the latest real-time information.

Pricing: Plus $20/month (100 times per month) / Pro $200/month (unlimited) / Team $25/user/month / Enterprise (contact sales)

Best for: Suitable for those performing research tasks requiring deep analysis, such as market or academic research. Also suitable for those who want to use it seamlessly from the ChatGPT interface.

4. Gemini Deep Research

Gemini Deep Research is an autonomous research feature provided by Google. In response to user queries, Gemini automatically investigates numerous web sources. It functions as an AI assistant that creates structured analytical reports based on the results.

• Strengths: Leverages Google Search's massive index for high-precision information gathering. Additionally, you can review and modify the research plan before investigation begins, allowing you to control the direction.
• Strengths: Generated reports can be exported directly to Google Docs. This enables seamless sharing and editing within teams.
• Things to note: According to AIpedia data, this is a feature included in Google One AI Premium ($19.99/month; the plan was renamed Google AI Pro in 2025). Please check the official website for the latest availability terms. Report generation takes several minutes.
• Things to note: Source investigation accuracy may be slightly lower for languages other than English, so please verify carefully.

Pricing: Included in Google One AI Premium $19.99/month / Workspace add-on (contact sales)

Best for: Suitable for those working in a Google Workspace environment who want to efficiently conduct broad research such as market or competitor analysis. Also suitable for business professionals who want to adjust the direction of their research themselves and obtain reports in an easy-to-share format.

5. ChatGPT Atlas

ChatGPT Atlas is an AI-native browser released by OpenAI in October 2025. ChatGPT is deeply integrated into the browser itself, allowing you to ask questions or summarize open pages from the sidebar. It also features Agent Mode, where the AI autonomously performs web operations to complete tasks.

• Strengths: Fully integrated with ChatGPT, enabling immediate questions and summaries of page content.
• Strengths: With Agent Mode, you can delegate autonomous web operations such as reservations or purchases to the AI.
• Strengths: The Browser Memory feature retains past browsing context, handling complex instructions.
• Things to note: Using Agent Mode requires a ChatGPT Plus subscription or higher.
• Things to note: Agent operations on financial or government sites are intentionally restricted.

Pricing: Free (basic browser features) / Agent Mode requires ChatGPT Plus $20/month or higher / Parallel Agent execution requires Pro $200/month

Best for: People who want to delegate everyday web tasks to AI, or those who need to process multiple agent tasks in parallel. However, caution is required in scenarios where human judgment is recommended for final decisions, such as important payments or transfers.

View details on ChatGPT Atlas features, pricing, and FAQ

6. Perplexity Comet

Perplexity Comet is an AI-native web browser developed by Perplexity. In addition to standard browser functions, it summarizes and analyzes pages in real time as you browse. This eliminates the need to switch between a browser and an AI chat interface, allowing information gathering to be completed on a single screen.

• Strengths: AI search and browsing are fully integrated, improving workflow efficiency.
• Strengths: Being Chromium-based, it is compatible with existing Chrome extensions.
• Strengths: You can get accurate answers with sources directly in the browser.
• Things to note: As a new service, it may have stability issues.
• Things to note: The accuracy of parsing Japanese pages may be lower than for English.

Pricing: Free (basic features) / Perplexity Pro $20/month for additional features

Best for: Ideal for those who frequently perform tasks involving information gathering, such as research, learning, or checking news. It is also suitable for business professionals who want to try a new AI-powered browsing experience while maintaining their traditional browser environment. If you plan to use advanced AI search features, Perplexity Pro ($20/month) is recommended.

7. Dia

Dia is an AI-native web browser developed by The Browser Company. It inherits the design philosophy of the Arc browser while being designed with AI as a core premise. It provides integrated support for browsing experiences such as search, summarization, and task execution.

• Strengths: You can ask questions or search using natural language in the address bar.
• Strengths: Supports automatic summarization of web pages, information extraction, and auto-filling forms.
• Strengths: Being Chromium-based, it is compatible with existing Chrome extensions. It also offers personalized suggestions based on browsing history and bookmarks.
• Things to note: As a new service, its features are still developing.
• Things to note: Japanese support is limited to certain areas. Switching from Chrome or Safari requires some adjustment, and you need to pay attention to how browsing data is handled (privacy).

Pricing: Free (basic features) / Pro version planned

Best for: Suitable for those who prioritize AI-assisted browsing or want to continue using existing Chrome extensions. However, please note that usage in Japanese is limited.

8. Kagi Search

Kagi Search is a premium search engine that excludes ads and trackers. It prioritizes privacy protection while also featuring AI-powered summarization. Its characteristics include category-based filtering of search results and detailed refinement options.

• Strengths: Completely zero ads and trackers, providing a clean search experience.
• Strengths: The "Lens" feature allows for highly customized search results. AI features are opt-in, meaning AI will not appear unless you activate it yourself. There is also a filter to exclude AI-generated images from search results.
• Things to note: The free plan is limited to 100 queries per month, so frequent use requires a paid plan.
• Things to note: Japanese search accuracy may be lower compared to Google.

Pricing: Free (100 queries/month) / Starter $5/month / Professional $10/month / Ultimate $25/month

Best for: People who prioritize privacy and want to search in an ad-free environment. It is also suitable for power users who want fine-grained control over search results using custom filters.

View Kagi Search features, pricing, and FAQ in detail

9. Brave Search

Brave Search is an AI-powered search engine that prioritizes privacy protection. It uses its own web index and does not track user search data. Additionally, the AI assistant “Leo” provides features such as page summaries and document analysis.

• Strengths: Complete privacy protection and a proprietary index independent of Google.
• Strengths: With the AI assistant Leo, you can choose from multiple AI models including Claude, DeepSeek, Gemma, Llama, and Qwen. Chat content is not saved or shared.
• Things to note: Japanese search accuracy and index coverage may be lower compared to major competitors.

Pricing: Free (with ads) / Premium $3/month (ad-free) / Leo Premium $15/month

Best for: People who want to avoid data tracking or try multiple AI models. However, if high-precision Japanese search is your top priority, you should compare and evaluate other tools.

View Brave Search features, pricing, and FAQ in detail

10. Phind

Phind is an AI search engine specialized for developers. It generates answers with source code for programming-related questions. Its feature is combining the latest web information with AI reasoning to provide practical code snippets.

• Strengths: Specialized in programming, offering high accuracy for technical questions. In addition to its proprietary Phind model, the Pro plan allows selection of GPT-4o or Claude.
• Strengths: A VSCode extension allows you to ask questions directly from the editor.
• Strengths: Answers include explicit source links, making it easy to verify reliability.
• Things to note: Not suitable for general questions outside of programming.
• Things to note: The free plan is limited to 10 requests per day.

Pricing: Free plan (10 requests/day, Phind model) / Pro $20/month (unlimited, GPT-4o/Claude available) / Team $30/user/month

Best for: Programmers and developers who want to streamline code creation and error resolution. Suitable for those working in a VSCode environment. However, the accuracy of referencing Japanese technical information may be lower compared to English.

Recommendations by Goal

Goal	Recommended tool	Reason
Try it for free first	Perplexity AI	Even the free plan is practical for basic searches, and every answer comes with sources.
Use it with Japanese text	Google AI Mode / ChatGPT Atlas	Both tools support Japanese in their UI and instructions, making them suitable for daily use.
Use it for work or teams	Gemini Deep Research / OpenAI Deep Research	Reports can be exported to Google Docs or PDF, making them easy to share.
Use it as a developer	Phind	It generates answers with code examples and can be used directly via the VSCode extension.
Search with privacy in mind	Kagi Search / Brave Search	Designed to exclude ads and trackers, allowing you to search while protecting personal information.
Leverage AI within the browser	ChatGPT Atlas / Perplexity Comet	Features real-time summarization and analysis of pages you are viewing.
Create in-depth research reports	OpenAI Deep Research	Automatically visits hundreds of web sources to generate comprehensive reports with citations.

The optimal tool depends on your purpose and familiar environment. Using multiple tools together can help balance search accuracy and work efficiency.

How to Choose Without Regrets

Select based on use case and research depth

Clarify whether you need simple information retrieval or autonomous research report generation. Perplexity AI offers reliable answers with sources and enables automatic deep-dive investigations via Pro Search. In contrast, OpenAI Deep Research and Gemini Deep Research specialize in creating comprehensive reports by automatically visiting hundreds of web sources.

• Quick checks: Perplexity AI, Google AI Mode
• In-depth research and report creation: OpenAI Deep Research, Gemini Deep Research

Pricing structure and availability of free tiers

Compare the limitations of free plans and the monthly fees of paid plans. Kagi Search offers a free tier limited to 100 uses per month, but its Starter plan is available from $5/month. Phind allows up to 10 uses per day on its free plan, but unlimited usage requires the Pro plan ($20/month).

• Free to use: Google AI Mode, Brave Search (with ads), ChatGPT Atlas (basic features)
• Low price range: Brave Search Premium ($3/month), Kagi Search Starter ($5/month)
• Standard paid plans: Perplexity Pro, ChatGPT Plus (OpenAI Deep Research), Phind Pro (all $20/month)

Japanese support accuracy and scope

Check the accuracy of Japanese searches and UI support. Perplexity AI and Google AI Mode support Japanese, but Perplexity AI may have lower accuracy in collecting Japanese sources compared to English. Dia and Kagi Search offer partial support, with English-centric UIs, and their Japanese search accuracy may be inferior to Google's.

• Japanese support: Perplexity AI, Google AI Mode, OpenAI Deep Research, Gemini Deep Research, ChatGPT Atlas
• Partial support: Perplexity Comet, Dia, Kagi Search, Brave Search, Phind

Usage environment and browser integration

If you want to use the tools outside of a web browser, check the supported platforms. Among AI-native browsers, Perplexity Comet and Dia support macOS and Windows, while ChatGPT Atlas supports macOS, Windows, iOS, and Android. Meanwhile, Perplexity AI and OpenAI Deep Research are available in a wide range of environments, including Web, iOS, and Android, and Phind also offers a VSCode extension.

• Dedicated browsers: ChatGPT Atlas, Perplexity Comet, Dia
• Multi-platform: Perplexity AI, Google AI Mode, OpenAI Deep Research, Gemini Deep Research
• Developer integration: Phind (VSCode extension)

If privacy is a priority, check for ads and trackers

If you want to avoid the collection of personal data, focus on privacy protection features. Kagi Search’s strength is that it has zero ads and trackers. Brave Search also features independence from Google through its own index and complete privacy protection. However, note that these may have lower Japanese search accuracy compared to Google.

FAQ

Q. Can I get by with free AI search engines?

Perplexity AI and Google AI Mode allow basic AI searches with their free plans. Kagi Search is free for up to 100 queries per month, but there is a usage limit. Phind is free for up to 10 queries per day, but unlimited access requires Pro at $20/month. If you have high usage frequency, you need to consider a paid plan.

Q. Which tool has the highest search accuracy in Japanese?

Perplexity AI and Google AI Mode support Japanese. However, Perplexity AI is considered weaker than English in its ability to gather Japanese sources. If you prioritize Japanese sources, Google AI Mode, which uses Google's search index, is a candidate. Kagi Search and Brave Search allow searching in Japanese, but their UIs are primarily in English, and Japanese search accuracy may be inferior to Google's. Phind has partial support, and its accuracy for referencing Japanese technical information is lower compared to English.

Q. Which tools can generate autonomous research reports?

OpenAI Deep Research and Gemini Deep Research provide autonomous research features. OpenAI Deep Research is available 100 times per month with Plus at $20/month, and unlimited with Pro at $200/month. Gemini Deep Research is included in Google One AI Premium ($19.99/month; now called Google AI Pro). Both may take several minutes to about 30 minutes to generate reports.

Q. Which tool is suitable if I prioritize privacy?

Kagi Search is a premium search engine with zero ads and trackers. It is available from Starter at $5/month and specializes in privacy protection. Brave Search also prioritizes privacy and is independent of Google due to its own index. The free plan includes ads, but Premium at $3/month removes them.

Q. Are there any recommended AI-native browsers?

ChatGPT Atlas fully integrates ChatGPT and allows autonomous web operations via Agent Mode. Basic features are free, but Agent Mode requires ChatGPT Plus at $20/month or higher. Perplexity Comet also integrates AI search and browsing and can be used with a free plan. Since it is Chromium-based, it supports existing Chrome extensions.

Q. Can I trust AI search answers as they are?

Don't take them at face value. As noted in the drawbacks of Google AI Mode, AI-generated answers need to be verified for accuracy. Perplexity AI and Deep Research attach source links to their answers, so please open the sources to verify important numbers and conclusions. For decisions involving health, money, or law, always confirm with a professional such as a doctor or lawyer.

Summary

This article compared 10 AI search engines, from Perplexity AI to Phind. Each tool excels in different areas, such as real-time web searches or autonomous research report generation. Pricing also varies widely, ranging from free-only options to those requiring paid plans of $20/month or more.

Japanese support and supported platforms (Web, iOS, Android, desktop apps, etc.) differ by tool. Additionally, the presence of privacy protection features and the degree of specialization for specific tasks are important selection criteria. Before adoption, it is important to clearly define your business workflows and the desired accuracy of answers.

• If you want accurate search results with sources: Perplexity AI (because source URLs are explicitly shown for all answers)
• If you want to automatically generate complex research reports: OpenAI Deep Research (because it visits hundreds of web sources to create comprehensive reports)
• If you prioritize privacy and want ad-free searches: Kagi Search (because ads and trackers are completely zero)

View all AI search engine tools (11 items)