What's Your IQ

QUESTION 1 / 15 · TYPES & VALUESEasy

What does this print?

print(0.1 + 0.2 == 0.3)

What this Python test measures, in short

This test checks whether you can predict what real Python code does: how values, names, collections, functions and objects behave at run time. It rewards knowing the language's rules over remembering library names.

Every snippet runs as shown on Python 3.10 or later. The questions are our own and are not standardised against a population, so treat the result as a check on your knowledge, not a certification.

By What's Your IQ · Reviewed 4 Oct 2026

Format: 15 predict-the-output questions, 4 options each
Topics: Types, collections, functions and scope, flow and comprehensions, objects and iterators
Version: Python 3.10+ (Python 2 reached end of life on 1 Jan 2020)
Language: Created by Guido van Rossum; first public release February 1991

THE IDEA BEHIND A THIRD OF THE QUESTIONS

Variables are labels, not boxes

In Python, b = a doesn't copy anything. It puts a second label on the same object. Step through the five lines and watch which object each name points to.

NAMES

a→ #1

OBJECTS IN MEMORY

#1 · list · named a[1, 2]

One list object (#1) is created and the name a is attached to it.

WHAT "PYTHONIC" MEANS

Same result, written the way Python intends

WORKS, BUT FIGHTS THE LANGUAGE

names = ["Ada", "Alan", "Grace"]for i in range(len(names)): print(i, names[i])

PYTHONIC

names = ["Ada", "Alan", "Grace"]for i, name in enumerate(names): print(i, name)

enumerate hands you the index and the item together, so there's no indexing to get wrong and the loop works on any iterable, not just lists.

2024Python became the most-used language on GitHubIt overtook JavaScript in GitHub's Octoverse report, driven largely by data science and machine-learning work.¹

1991First release. Guido van Rossum published Python 0.9.0, naming it after Monty Python's Flying Circus rather than the snake.²

2008 → 2020The long switch. Python 3.0 broke compatibility on purpose (print became a function, text became Unicode). Python 2 was finally retired on 1 January 2020.³

Since Oct 2021Top of TIOBE. Python has held first place in the TIOBE popularity index, which counts search-engine results for each language.⁴

2024 surveyAbout half of developers. Roughly 51% of respondents to Stack Overflow's survey had used Python in the past year, second only to JavaScript.⁵

GitHub. (2024). Octoverse 2024: AI leads Python to top language as the number of global developers surges.
Python Software Foundation. History and License. Python documentation.
Python Software Foundation. (2020). Sunsetting Python 2.
TIOBE Software. TIOBE Programming Community Index.
Stack Overflow. (2024). 2024 Developer Survey: Technology.

Where to go next

SQL testMost Python data work ends in a database query. The SQL test covers joins, grouping and window functions, the parts pandas users reach for most.

JavaScript testJavaScript shares Python's label-not-box model for objects but has very different rules for equality and scope. A good test of whether you know the rules or just the syntax.

All programming testsTwelve languages and five frameworks, each with its own question set. Pick the stack you use at work or the one you're learning next.

Read the code. Predict what Python does.