Which AI to use when (Claude, ChatGPT & friends)

The big assistants overlap but have genuinely different strengths and personalities. You don't need the single 'best' one — you need a small mental map of which to reach for. Picking right gets noticeably better answers and saves money, because you're not paying for a premium model to do a task a cheaper one handles fine.

Writing or careful thinking goes to Claude; quick everyday tasks and a bit of everything go to ChatGPT; very long documents go to Gemini; real images go to an image model. These aren't about which company is 'winning' — they're about fit. A hammer isn't better than a screwdriver. Treating it that way immediately makes you more effective than someone forcing every task through one favourite.

For anything that matters, paste the same prompt into two assistants and compare — it takes thirty seconds and routinely surfaces a clearly better answer, or a useful second angle. Build the habit of asking 'which of my tools fits this best?' instead of opening the same one on autopilot. Within two weeks it becomes automatic, and you'll have a real edge over people who never developed the instinct.

Any specific ranking of models is out of date within months — new versions launch and leapfrog constantly. If you anchor your whole workflow to 'Model X is best', you'll be wrong by next quarter. What doesn't go stale is the habit: match the job to the tool, keep two open, and re-check your assumptions every so often as new models ship.

1. 1Writing/thinking → Claude; quick everyday → ChatGPT; long documents → Gemini; images → an image tool.
2. 2For important work, paste the same prompt into two and compare.
3. 3Don't marry one tool; pick a default per kind of task.
4. 4Re-check your defaults every few months as models change.

Prompts to compare and choose