Beginner

AI bias: when machines repeat our blind spots

AI bias is a systematic error that leads a system to treat some people less fairly or to repeat stereotypes. It usually comes from the data the AI learned from, and its effects can be very real.

Data as of October 22, 2026

Key figures

LevelBeginner

An error that isn’t random

Every AI gets things wrong sometimes. We call it bias when the errors are not random but keep hitting the same groups, or when the AI repeats clichés. A face recognition system that fails more often depending on skin tone, a résumé screening tool that rejects certain profiles more often, an image generator that almost always draws a “doctor” as a man: these are biases.

The most cited example is the Gender Shades study by Joy Buolamwini and Timnit Gebru, published in 2018 (Gender Shades paper). It measured that three commercial face analysis systems performed far worse on darker-skinned women than on lighter-skinned men. One cause it pointed to: benchmark datasets made up overwhelmingly of lighter-skinned faces.

Where bias comes from

  • Training data that is lopsided or reflects past inequalities.
  • Human choices: what gets measured, what counts as a “good” answer, which cases nobody thought to test.
  • Use: a tool designed for one context, then applied to a different population.

Why it matters to you

In daily life, bias can be subtle: a translation that always defaults to the masculine, a job ad draft that leans on stereotypes. At work, the stakes are higher if AI helps hire, grade or allocate support. Before handing a decision to a tool, ask who might be disadvantaged and plan for a human check. The Can I trust an agent with this? tool helps you weigh that kind of risk.

In Europe, the EU AI Act and the GDPR regulate these uses, and data protection authorities publish guidance for developers.

Common misconceptions

“A machine is objective by definition.” It reflects its data and the choices of the people who built it.

“Just remove gender or ethnicity from the data.” Other details (first name, zip code, career path) can play the same role indirectly.

“Bias is the same as a hallucination.” A hallucination is made-up information; bias is a repeated imbalance. Both can happen at once.

These questions belong to the wider field of AI ethics.

Related terms

Try it

Full glossary

Frequently asked questions

Where does AI bias come from?

Mostly from the training data: if some groups are rare or shown in a stereotyped way, the model reproduces that imbalance. Design choices (the goal, the criteria, the tests) can also introduce bias or help correct it.

Is there a well-documented example of AI bias?

The Gender Shades study, published in 2018 by Joy Buolamwini and Timnit Gebru, evaluated three commercial systems that classify gender from faces. It found that darker-skinned women were the most misclassified group, while errors for lighter-skinned men were very rare.

Can an assistant like ChatGPT be biased?

Yes. Providers add guardrails, but an assistant may still offer stereotyped examples, know some cultures or languages better than others, or present a topic from a single angle. Stay critical, especially on sensitive subjects.

Are there laws about AI bias?

In Europe, partly. The GDPR protects against certain fully automated decisions, and the EU AI Act sets data quality requirements for so-called high-risk systems, such as those used in hiring. Rules differ by country, so for a specific case, ask a legal professional.

Data sources

Data as of October 22, 2026

Report an error

Does a figure, a date or a fact look wrong? Tell us: every report is checked.