【2026年最新版】プロが徹底比較！個人・法人向け四大AIツールの選び方と導入コストの真実 　[2026 Latest Edition] The Ultimate Pro Comparison! How to Choose the “Big Four” AI Tools for Individuals & Businesses and the Truth About Costs

Hello! Recently, not a day goes by without hearing the word “AI” in both business and our private lives. Many of you might be wondering, “I want to introduce it to our company,” or “Which one should I pay for personally?”

I will provide a completely objective perspective to help you choose the best tool for your needs.

Currently, the “Big Four AI Tools” that serve as powerful partners in business and daily life are ChatGPT, Claude, Copilot, and Gemini. From their respective pros and cons to the most pressing question—”implementation costs (comparing their highest-performance plans)”—I will explain everything clearly from a professional standpoint.

1. The Big Four AI Tools: Pros and Cons

First, let’s look frankly at what each tool is “good at” and what it “struggles with.”

① ChatGPT (Developed by: OpenAI)

[The Strongest All-Rounder with Overwhelming Popularity]

• Pros: A versatile player that performs everything at a high level, from conversation and writing to data analysis and image generation. It has the largest user base, meaning the internet is flooded with tips and know-how, making it the most beginner-friendly. Its ability to create custom, company-specific AIs called “GPTs” is also highly powerful.
• Cons: Because it has so many features, users can sometimes feel overwhelmed about where to start. Additionally, the text it generates can sometimes feel a bit “mechanical” or “AI-like.”

② Claude (Developed by: Anthropic)

[Leave Natural Languages and Reading Massive Documents to This One]

• Pros: Its phrasing is simply beautiful, generating warm, natural text that reads as if a human wrote it. Furthermore, its ability to read and accurately process massive amounts of text data at once—such as thick PDF manuals or lengthy meeting transcripts—is second to none. It also excels highly in generating programming code.
• Cons: It does not come with image generation capabilities by default. Also, its integration with external tools, such as web search functions, is somewhat modest compared to the others.

③ Copilot (Developed by: Microsoft)

[The Business Person’s Right Hand, Specialized in Office Integration]

• Pros: Its greatest strength is that it works directly within the Microsoft products you already use—summarizing documents in Word, creating charts in Excel, and recapping Teams meetings. For corporate implementation, its high reliability in terms of compliance and security is a major selling point.
• Cons: To use its full features (like Copilot for Microsoft 365), you must pay an additional fee on top of your existing Microsoft 365 license, which can make running costs relatively high.

④ Gemini (Developed by: Google)

[The Lightning-Fast AI that Connects Seamlessly with Google Services]

• Pros: Its integration with Google Workspace (Gmail, Google Docs, Google Drive, etc.) is remarkably strong. It accesses the latest information exceptionally fast and excels at feats like summarizing YouTube videos. Its processing speed is top-tier.
• Cons: Occasionally, the formatting of its answers can break, and it tends to have more “variance” (returning a slightly different tone for the same question) compared to other tools.

2. A Direct Comparison! The Reality of Implementation Costs and “Highest-Performance Plans”

When it comes down to actual implementation, “money” is the biggest concern. Currently, most tools offer “Free Plans” or “Standard Paid Plans (around 3,000 JPY/month).” However, this time, we will dare to focus our comparison on the “Highest-Performance Plans for individuals and companies who want to use AI aggressively on the front lines” (Prices may vary due to exchange rates).

Highest-Performance Plans for Individuals (For Heavy Users & Researchers)

A recent trend is the emergence of ultra-premium plans for individuals seeking “advanced reasoning” or “near-limitless usage.”

• ChatGPT Pro / Claude Max 20x, etc.: Approx. 30,000 JPY/month ($200) This is a staggering 10 times the price of standard plans (approx. 3,000 JPY). This pricing is strictly for professionals who want to “have AI help with complex programming all day” or “process massive amounts of advanced mathematical calculations and research data.” For general use, a standard plan is plenty, but for those who want to push AI to its absolute limits, this is the pinnacle.
• Gemini Advanced / Copilot Pro: Approx. 2,900 JPY to 3,200 JPY/month Currently, these platforms do not offer a multi-ten-thousand-yen tier for individuals; instead, they allow access to their highest-performance models for around 3,000 JPY per month.

Highest-Performance Plans for Corporations (For Enterprise & Team Implementation)

When implementing AI as a company, security (e.g., ensuring input data isn’t used to train the AI) and employee account management features are absolute requirements.

• Enterprise Plans for Large Corporations: Custom Quotes Large-scale rollouts like “ChatGPT Enterprise” or “Claude Enterprise” require custom quotes tailored to the company’s specific needs, featuring high-level security and massive usage limits.
• For SMEs and Teams (Using Top-Tier Models): Approx. 3,500 JPY to 4,500 JPY per user/month
  • ChatGPT Team / Claude Team: From approx. 3,800 JPY ($25) per user/month. These can be implemented starting with just a few people, allowing teams to share a secure chat environment.
  • Gemini Enterprise: For Google Workspace users, running just over 4,500 JPY per user.
  • Copilot for Microsoft 365: 4,497 JPY per user/month (Requires a separate Microsoft 365 license).

[The Verdict on Costs] For individuals, the golden rule is to start with a standard paid plan at “3,000 JPY/month.” Only professionals who constantly hit usage limits should consider the 30,000 JPY plans. For corporations, the most cost-effective and secure method right now is to contract a Team plan for the required number of users at “around 4,000 JPY per user/month,” which effectively prevents information leak risks.

3. Summary: Which AI is Best for You? [Choosing for Individuals vs. Corporations]

We’ve compared them objectively so far, but what do you think? Finally, we have organized the best ways to choose a tool based on whether you are using it as an “Individual” or implementing it as a “Corporation (Organization).”

[The Individual Perspective] Choosing Based on Lifestyle and Daily Tasks

When considering a paid plan as an individual, the standard is how much you want to elevate the “quality of your output.”

• If you want a versatile daily partner or help with creative side gigs → ChatGPT Plus It covers most of what an individual wants to do, from writing blog posts and managing SNS to generating images and light programming. Because of its massive user base, it’s very easy to search for usage tips (prompts) online, which is a huge advantage for personal use.
• For reading long texts, serious writing, or as a study partner for upskilling → Claude Pro When it comes to tasks like “reading a whole book and summarizing it” or “explaining a difficult textbook for a certification exam,” Claude is second to none. It is also highly recommended for individual creators who want to write novels or publish information in highly natural language.
• For managing private schedules or “lightning-fast searches” on your smartphone → Gemini Advanced Beyond its great synergy with Android smartphones, it integrates with Google Maps, YouTube, and Gmail to handle casual daily requests like, “Plan a weekend trip for me and check the routes,” with unparalleled speed.

[The Corporate Perspective] Choosing Based on Existing IT Environments and Security

When a corporation implements AI, the focus shouldn’t be on “personal preference,” but rather on “whether it connects with the company’s existing systems” and “whether it clears information leak (security) risks.”

• Companies that have already rolled out “Microsoft 365” company-wide → Copilot for Microsoft 365 This is the best choice. Because AI is built directly into Word, Excel, and PowerPoint, the cost (and time) required to train employees on a new tool is minimized. The Teams meeting summarization feature alone is worth the investment.
• Companies that base their operations on “Google Workspace” → Gemini Enterprise If your company regularly shares files via Gmail, Google Drive, and Google Docs, Gemini is the clear winner. You can streamline your workflows in a secure environment while leveraging your existing cloud setup.
• Companies looking to develop “custom internal AI tools” or prioritize writing quality → ChatGPT Team or Claude Team If your company isn’t tied to a specific IT infrastructure (like Microsoft or Google), or if you want to share custom AIs (like GPTs) to automate routine internal tasks across a team, ChatGPT is the easiest to handle. Alternatively, for departments like Marketing or PR where “writing quality” directly impacts business results, implementing Claude’s Team plan specifically for them can be highly effective.

Finally… What are you doing with old PCs you no longer need after implementing AI?

To ensure these new AI tools run smoothly and comfortably, an increasing number of companies and individuals are upgrading their office PCs to the latest models. But that leads to a surprising problem: “How do we dispose of our old computers?”

When it comes to disposing of PCs containing confidential and personal information, please leave it to S&T! From secure data erasure to proper recycling, our professionals—equipped with flawless security measures—will dispose of your devices safely and swiftly, saving you all the hassle. As you look forward to an exciting future with new AI, S&T will fully support you in cleaning up and organizing your office tech. Please feel free to consult with us anytime!