TL;DR
For office work, the right AI tool depends less on benchmark scores and more on where you already spend your day:
- Live in Gmail / Docs / Sheets / Slides? Buy Google AI Pro ($19.99/mo). Gemini is already in the side panel of every Workspace app.
- Live in Outlook / Word / Excel / Teams? Buy Microsoft 365 Copilot ($30/user/mo, enterprise). It is grounded on your tenant’s email, files, and meetings.
- Do a lot of writing and read long documents? Buy Claude Pro ($20/mo). A 1M-token context window means a whole board pack fits in one prompt.
- Want the most flexibility — Custom GPTs, Code Interpreter, image gen? Buy ChatGPT Plus ($20/mo).
Most people need exactly one of these, plus maybe one “thinking” tool on top. All prices are individual/consumer tiers as of June 2026.
The four products at a glance
| ChatGPT | Claude | Gemini | Microsoft Copilot | |
|---|---|---|---|---|
| Maker | OpenAI | Anthropic | Microsoft | |
| Entry paid tier | Plus $20/mo | Pro $20/mo ($17/mo annual) | AI Pro $19.99/mo | M365 Copilot $30/user/mo |
| Default model | GPT-5.5 | Sonnet 4.6 | Gemini 3.1 Pro (3 Flash for light tasks) | OpenAI + Microsoft models via Graph |
| Context window | ~320 pages in-app (full 1M only on $200 Pro) | 1M tokens | 1M tokens | Tenant-grounded retrieval |
| Best home turf | General flexibility | Long-doc reading + writing | Google Workspace | Microsoft 365 |
| Top consumer tier | Pro $100 / $200 | Max $100 / $200 | AI Ultra $99.99 | — |
Prices and models are individual/consumer tiers as of June 2026. Sources: OpenAI pricing, Claude pricing, Google AI plans, Microsoft 365 Copilot pricing.
What each is actually best at for office work
The four products look similar on the price page; their day-to-day behavior is not.
ChatGPT (Plus / Pro)
What you get: Plus ($20/mo) runs GPT-5.5 by default — the in-app picker is Instant / Thinking / Pro — plus Custom GPTs, Canvas, file upload, image generation, and Code Interpreter. The Pro tier has two rungs ($100 mid-tier and $200), and the full 1M-token in-app context plus heavier reasoning is reserved for the $200 plan. The US Free tier shows ads as of February 2026.
Office strengths:
- General-purpose writing across tones and formats.
- Custom GPTs that codify a recurring office prompt — the same “intern,” every time.
- CSV and spreadsheet analysis via Code Interpreter, which runs Python on the file you upload.
- Image generation for slides, social posts, and one-off decks.
- Canvas for collaborative editing of a long doc or code file.
Two concrete office tasks:
- Build a Custom GPT named “Weekly Status Rewriter” that takes raw bullets and returns a team update in your house format. Reuse it every Friday.
- Drop a 100k-row CSV into a chat and ask:
Find the top 5 quality issues by region.
Return a table plus a bar chart.
Use the column "defect_rate" for ranking.Loses on: native Google Workspace integration (Gemini wins); deep Microsoft 365 grounding (Copilot wins); the biggest single-prompt documents on a $20 plan (Claude wins, since ChatGPT’s full 1M window needs the $200 Pro tier).
See our deeper ChatGPT vs Claude vs Gemini breakdown for the model-by-model picture.
Claude (Pro / Max / Team / Enterprise)
What you get: Pro ($20/mo, or $17/mo billed annually) runs Sonnet 4.6 with a 1M-token context window, file uploads, and Projects (a per-project knowledge base). As of 2026, Pro also bundles Claude Code and Claude Cowork. Max ($100 for 5x usage, $200 for 20x) adds far more Opus 4.7 headroom — the model that scores 87.6% on SWE-bench Verified.
Office strengths:
- Long-document reading — drop a whole 200-page PDF into one prompt and it fits.
- Polished long-form writing, with careful editing and low hallucination rates.
- Artifacts render code, HTML, and diagrams inline in the right pane.
- Projects keep a meeting series, product spec, or brand voice in one place; every new chat in that Project inherits the context.
Two concrete office tasks:
- Attach a full 80-page board pre-read and ask:
Summarize the pre-read in one page.
Then list the 6 questions a non-executive director should raise.- Set up a Project called “Q3 Planning” with all OKRs, the last six weekly statuses, and your team’s brand voice. Every chat inside the Project already knows the context.
Loses on: live web search (less native than ChatGPT or Gemini); image and video generation; deep Workspace or M365 integration.
Gemini (Google AI Pro / Ultra)
What you get: AI Pro ($19.99/mo, formerly “Gemini Advanced” / “Google One AI Premium,” renamed early 2026) puts Gemini 3.1 Pro with a 1M-token context inside Gmail, Docs, Drive, Sheets, and Slides, plus the standalone Gemini app. As of March 2026, lighter Workspace tasks default to Gemini 3 Flash, with 3.1 Pro handling complex reasoning. AI Ultra ($99.99/mo) adds the full Veo 3.1 video model, longer Deep Research, and higher rate limits.
Office strengths:
- In-Workspace assistance — Gemini reads your Gmail thread for context, expands a Docs outline into a draft, builds Sheets formulas, and drafts Slides decks.
- Deep Research output drops straight into a Google Doc with citations.
- Veo 3.1 for short-form video; NotebookLM Audio Overviews turn source docs into a podcast.
Two concrete office tasks:
- In Gmail, on a long thread: “Draft a reply that politely declines the meeting and proposes a Q4 follow-up.”
- In Sheets:
@Gemini build a formula in column C that returns
the rolling 4-week average of column B.Loses on: Custom-GPT-style automation (ChatGPT wins); the most polished long-form writing (Claude wins); developer tooling.
Microsoft Copilot (M365 Copilot)
What you get: Two very different products share the name. Microsoft 365 Copilot ($30/user/mo enterprise; Business is $18/user/mo on promo through June 30, 2026, then $21) is grounded on your tenant’s email, files, and meetings through Microsoft Graph, and lives inside Outlook, Word, Excel, PowerPoint, Teams, and Loop. For individuals, the old standalone Copilot Pro is gone — it now ships inside Microsoft 365 Premium ($19.99/mo), which adds Copilot to the desktop Office apps but does not touch business data. Copilot requires a qualifying base Microsoft 365 license.
Office strengths:
- Outlook: “draft a reply, formal tone, two paragraphs.”
- Word: “rewrite this section more concise” or “add a 1-paragraph executive summary at the top.”
- Excel: “add a column with YoY%” or “highlight rows where revenue dropped more than 10% MoM.”
- PowerPoint: “build a 10-slide deck from this Word doc.”
- Teams: meeting recap with action items, decisions, and speaker attribution.
Two concrete office tasks:
- After a 1-hour Teams meeting: “What did marketing commit to and by when? List owner + due date.”
- In Excel on the monthly revenue tab:
Highlight rows where revenue dropped more than 10% MoM.
Add a column with YoY%.Loses on: anything outside the M365 tenant; image and video generation; raw reasoning depth (lags ChatGPT Pro and Claude Max on hard problems).
One-line picker
- Live in Google Workspace → Gemini (Google AI Pro, $19.99).
- Live in Microsoft 365 → Copilot (M365 Copilot, $30/user enterprise; Premium $19.99 for solo).
- Lots of writing and long documents → Claude Pro ($20).
- Maximum flexibility, Custom GPTs, Code Interpreter → ChatGPT Plus ($20).
How to choose, step by step
- List your weekly office tasks and group them: writing, reading, summarizing, calculating, scheduling, communicating.
- For each group, run the same prompt across the two most plausible candidates — ChatGPT Custom GPT vs Claude Project for writing; Claude vs Gemini Deep Research for long-doc summaries; Gemini in Sheets vs Copilot in Excel for formulas; Copilot in Teams vs a manual transcript paste into ChatGPT for meeting recaps. Compare on accuracy, speed, format fit, and copy-paste ease.
- Match tools to your dominant environment, not to a feature list. If 80% of your day is Gmail / Docs / Sheets, default to Gemini. If 80% is Outlook / Word / Excel / Teams, default to Copilot. Then add ChatGPT or Claude as your “thinking” tool on top.
- Stack-test: pick your top two, use them in parallel for two weeks, and track which one you reach for first.
- Drop the one you barely opened. Renew the survivor.
- Re-check every quarter — models and features at this price point move fast.
Common mistakes
- Subscribing to all four. You will use two.
- Picking by feature list instead of by your real tasks.
- Never re-evaluating. The leader from a year ago may not be today’s.
- Buying M365 Copilot at $30/user without a qualifying base Microsoft 365 license — it cannot be bought standalone.
FAQ
- Can the free tiers carry me? For light office use, yes. ChatGPT Free runs GPT-5.5 (with tight daily limits and US ads since Feb 2026), Claude Free gives limited Sonnet 4.6, and Gemini’s free app covers basic drafting. Heavy use — roughly 50+ chats a week, or long documents — pays back one paid tier quickly.
- Is M365 Copilot worth $30/user? Only if your team lives inside Microsoft 365 daily and you want answers grounded on your own email, files, and Teams meetings. For a solo user who just wants AI in desktop Office, Microsoft 365 Premium at $19.99/mo is the cheaper route; for pure flexibility, ChatGPT Plus at $20 wins.
- What’s the cheapest way to get a 1M-token context window? Claude Pro at $20/mo (or $17/mo annual) and Google AI Pro at $19.99/mo both include a 1M-token window. ChatGPT’s full 1M in-app context is reserved for the $200 Pro plan as of June 2026.
- I use both Google and Microsoft. Which AI first? Buy for the side that owns your hairy stuff — calendar, shared files, ongoing projects. The other side can wait a quarter; feature parity tends to close fast.