Claude, GPT or Gemini: which AI model to use for each task

By Infinithink Studio · October 28, 2026

Claude vs GPT vs Gemini is the comparison most teams run into once AI becomes part of daily work. Each family comes from a different company, OpenAI for GPT, Anthropic for Claude and Google for Gemini, and each has its own strengths. The useful question isn't which one is "the best". It's which one fits the task in front of you, and how to check it in ten minutes instead of reading benchmarks.

This guide gives you a practical way to choose, a short test you can run on your own work and the mistakes that make a good model look bad.

Why one model is rarely enough

Models are trained and tuned differently, so they behave differently on the same request. One writes tighter emails, another keeps the thread across a forty-page contract, another is better at structured analysis of a long source. Providers also release new versions several times a year, and results can change with them.

Teams that stick to one model tend to blame "AI" for results that are really a mismatch between the task and the model. Teams that can switch per task find the right model for each job more easily and cut rewrites. That's the case for a multi-model AI chat: one place, several models, and the habit of choosing.

Claude vs GPT vs Gemini: a starting map

These are starting points from everyday use, not fixed rules. Test them on your own material.

• GPT (OpenAI) is a general-purpose option for everyday drafts, quick replies, brainstorming and short rewrites. Its smaller models are faster and cost less, which can make them a sensible default for routine work.
• Claude (Anthropic) is worth trying for long documents, careful editing and writing that needs a consistent tone, including writing in Italian. In our use it follows detailed instructions closely, but test it on your own material.
• Gemini (Google) is worth trying with long source material and analysis-heavy tasks, such as comparing several documents or pulling the key points out of a long report.

Every family also comes in sizes. Smaller models answer faster and cost less, larger ones reason better on hard tasks. A good rule is to start small and move up only when the answer isn't good enough.

Which AI model for which task

Emails, posts and short copy

Start with a standard GPT model. If the text sounds generic, run the same brief on Claude and compare the two versions side by side. Keep the one that needs fewer edits.

Long documents, contracts and reports

Try Claude or Gemini first. Ask for a summary with section references, then ask a precise follow-up question. A model that points you to the right section is more useful than one that writes a fluent summary you can't check.

Analysis and comparisons

Give the model a table or a clear structure to fill: options in rows, criteria in columns. Gemini and the larger Claude and GPT models are worth testing for this. Ask it to state what it couldn't find, so gaps don't turn into guesses.

Writing in Italian or another language

Write the brief in the target language and include one example of the tone you want. Compare two models on the same brief. Small differences in phrasing matter more to a native reader than any benchmark.

Code snippets and spreadsheet formulas

Claude and GPT are both worth testing here. Say exactly where the code will run, for example "formula for Google Sheets" or "Python 3 script", and test the result on a copy of your data.

A ten-minute test to pick your default model

1. Pick three real tasks from last week, for example one email, one summary of a long document and one piece of analysis.
2. Write one brief per task with the goal, the audience, the length and one example of the result you want.
3. Run the same brief on two or three models without changing a word.
4. Score each answer on two things only: how many edits it needs and whether every fact checks out.
5. Write down the winner per task and share the list with your team. Repeat the test when a provider releases a new version.

Mistakes that make a good model look bad

• Vague briefs. "Write a post about our offer" gives generic text on any model. Give the audience, the goal and the facts.
• Using the largest model for everything. It costs more and isn't always better on simple tasks.
• Not checking facts. Every model can state wrong things with confidence. Names, numbers, dates and quotes need a human check.
• Pasting personal data you don't need. Remove names and details that aren't required for the task, and follow your company's rules on what can go into an AI tool.

One workspace for several models

Paying for three separate subscriptions to compare models adds up quickly and splits your work across three apps. In Infinithink you choose the model in each chat. The all-in-one AI assistant puts GPT, Claude and Gemini in one place, depending on your plan, and the AI model comparison lists which models each plan includes. The same models also power the AI writer, so a brief that works in chat works in your writing tools too.

Compare models on your own work, in one place. Start free. The Free plan adds 150 credits every month and needs no credit card. See pricing

Frequently asked questions

Is Claude better than GPT?

It depends on the task. Neither is better in general, each suits different tasks. Run the same brief on both and keep the one that needs fewer edits.

Which AI model is best for business?

There isn't a single best one. Most businesses do well with a fast standard model as the default and a more capable model for long documents and analysis.

Can I use Claude, GPT and Gemini with one subscription?

Yes, with a multi-model workspace. On Infinithink the Free plan uses GPT models, and paid plans add Claude and Gemini. The model comparison page lists the models in each plan.

Do larger models always give better answers?

No. On simple tasks a smaller model is often just as good and much faster. Move up when the answer misses the point or the task needs careful reasoning.

How often should I re-test the models?

Whenever a provider releases a new version you plan to use, and at least every few months. Keep your three test briefs so the comparison stays fair.

For information only, this is not legal or professional advice. Information is current as of the publication date and may change. Official sources checked on October 28, 2026.