# Ask an AI for a number between 1 and 10, and you get 7

> I asked ChatGPT and Claude for a random number between 1 and 10. Both picked 7. And it turns out we humans do exactly the same.

Published: 2026-10-15 · Facts checked on 2026-10-15
URL: https://sobra.be/en/nostrabramus/ai-picks-7/

Ask a chatbot for a random number between 1 and 10, and chances are you'll get 7. I tried it in ChatGPT and in Claude Opus 5.5, each in a fresh conversation, and got the same answer twice, straight away: 7.

That's no coincidence. In a [2025 study](https://arxiv.org/abs/2502.19965), GPT-4o-mini, Phi-4 and Gemini 2.0 picked 7 in about 80% of cases, and 7 was the favourite of all six models tested.

The funny part is that we humans do it too. When [YouGov](https://yougov.com/en-gb/articles/51866-seven-is-the-most-random-number) asked Britons for a random number between 1 and 10, a third picked 7, where pure chance would give you 10%. 7 simply feels random: it isn't an extreme, it isn't the middle and it isn't even. The models most likely picked up that habit from us.

So if you need to draw a winner for a contest, don't leave it to a chatbot.

## Sources

- [Deterministic or probabilistic? The psychology of LLMs as random number generators (Coronado-Blázquez, arXiv)](https://arxiv.org/abs/2502.19965)
- [Britons most likely to pick 7 as 'random' number (YouGov)](https://yougov.com/en-gb/articles/51866-seven-is-the-most-random-number)