Does Reading Increase IQ? What It Does and Doesn't Do
Does reading increase IQ? It helps one part of it: verbal IQ. Reading builds vocabulary, background knowledge and comfort with complex sentences, all of which show up on verbal test questions. What it does much less for is number, pattern and logic reasoning, which need their own practice.
If you read a lot but still struggle with the non-word parts of reasoning, IQ Tester can show you exactly which skill is lagging. Find my weak spots
Short answer
Picture your reasoning as a set of muscles. Reading is a great workout for some of them and skips others entirely.
What reading tends to build:
- Vocabulary
- General knowledge
- Understanding of long, tricky sentences
- Comfort with abstract ideas
- Attention span (if you read without your phone buzzing)
What reading tends not to build much on its own:
- Mental arithmetic
- Spotting rules in shape or number patterns
- Holding several steps in your head at once
So, does reading make you smarter? In the verbal sense, yes, it very likely helps. In the "better at everything" sense, not by itself.
Verbal IQ vs reasoning
To understand whether reading actually increases IQ, you need to know what a test is measuring.
Verbal IQ meaning
Verbal questions test word knowledge and word relationships. Think analogies ("hot is to cold as tall is to...") or picking the word that doesn't belong. Knowing more words and more facts gives you a direct advantage.
Reasoning that isn't about words
Other questions ask you to find a hidden rule in a grid of shapes, continue a number series, or follow an "if A then B" chain. Knowing more words helps a little with understanding the instructions, but the core skill is different.
| Skill on the test | Does reading help? | What helps more |
|---|---|---|
| Vocabulary and analogies | Yes, a lot | More reading, especially varied |
| General knowledge | Yes | Non-fiction, curiosity |
| Number series | Not much | Mental math practice |
| Shape patterns | Not much | Pattern drills, naming the rule |
| Logic chains | A little | Step-by-step logic practice |
This is why psychologists often split intelligence into crystallized (what you know) and fluid (solving new problems). Reading mostly feeds the first.
What the twin study found
The clearest evidence comes from a 2015 study in Child Development by Stuart Ritchie, Timothy Bates and Robert Plomin. They followed nearly 2,000 pairs of identical twins in the UK from age 7 to 16.
Why twins? Identical twins share their genes and usually their home, so if one twin reads better than the other, genes and family can't explain the difference.
What they found:
- The twin who was the stronger early reader tended to score higher on later verbal intelligence tests.
- There were also hints of a link to nonverbal reasoning, though weaker.
It's a single study, and it's about children, so don't stretch it too far. But it's good evidence that reading ability doesn't just reflect intelligence. It seems to feed it, at least in the verbal direction.
Does reading increase IQ in adults?
There's less direct research on adults. Adult vocabulary keeps growing across life, and reading is one of the main ways people learn new words, so it's reasonable to expect verbal skills to keep benefiting. Just don't expect big jumps in pattern or number reasoning.
Fiction vs non-fiction
Does reading fiction increase IQ more than non-fiction? There's no strong evidence that one type raises IQ more. They just train different things.
Fiction is good for:
- Following long, layered plots (a light memory workout)
- Understanding people's motives and points of view
- Rich, varied vocabulary
Non-fiction is good for:
- Building background knowledge
- Following arguments and evidence
- Learning technical words in science, history and tech
The best books to get smarter are the ones slightly harder than what you're used to. Not so hard you give up, but hard enough that you look something up every few pages.
How to read for reasoning
Reading every day can increase what you know. Reading actively is what trains thinking. Here's how to read for understanding instead of just turning pages.
1. Read with a question
Before you start a chapter, write one question you expect it to answer. At the end, answer it in two sentences.
2. Stop and predict
In fiction, pause at a cliffhanger and predict what happens next and why. In non-fiction, predict the author's next point. Checking your prediction is a small reasoning exercise.
3. Explain it out loud
Tell someone, or just your empty room, what you just read in 30 seconds. If you can't, you skimmed. Putting reasoning into words is a skill of its own, and a common weak spot.
4. Hunt for the argument's weak link
In an opinion piece, find the one claim the whole argument depends on. Is there evidence for it?
Here's the honest part: after doing all this, you might still not know if your reasoning is getting better or where it breaks down. Is it vocabulary? Working memory? Attention? Judging your own thinking is hard.
IQ Tester takes that guesswork away. Its 16 quick questions pin down which of 7 problems is holding you back, including putting reasoning into words, scattered attention and pattern spotting. Then you get a daily 10-minute drill, like "Name the rule out loud," aimed at your weak spot. Find my weak spots
A reading habit that sticks
Reading every day beats reading a lot once a month. Some reading habit tips that actually work for teens:
- Tie it to something you already do. Ten pages right after dinner, or on the bus.
- Phone in another room. Reading also trains focus, but only if you let it.
- Keep a word list. One new word per session. Use it in a sentence the next day.
- Quit bad books. Life's short. Switch if you dread opening it.
- Mix it up. One novel, one non-fiction book, alternating.
If you want an evidence-backed look at other habits, see how to get smarter as a teenager, and for why schooling matters so much, read can IQ change over time.
Pair your reading with the skills it misses
Does reading increase IQ? It strengthens your verbal side, so keep going. In the next two minutes, IQ Tester shows you which non-reading skills need work, gives you a reasoning tier, and starts you on a daily 10-minute drill covering pattern, number, verbal and logic problems.
FAQ
Does reading increase verbal IQ?
Very likely, yes. Reading builds vocabulary and knowledge, which are exactly what verbal questions test. A large UK twin study found the twin who read better early on tended to score higher on verbal tests later.
Does reading books increase IQ more than reading online?
There's no solid evidence comparing the two directly. Books tend to be longer and more focused, which trains attention better than jumping between short posts and notifications.
Does reading fiction increase IQ?
Fiction helps with vocabulary and following complex stories, but there's no strong evidence it raises IQ more than non-fiction. Reading a mix is a good plan.
Does reading every day increase IQ?
Daily reading steadily grows your vocabulary and knowledge over time, which supports verbal reasoning. It won't do much for number or pattern skills on its own, so practise those separately.
Does reading actually make you smarter, according to Reddit?
Reddit threads mostly agree that reading helps vocabulary and knowledge but not "raw" problem solving. That matches the research reasonably well: reading feeds verbal intelligence more than fluid reasoning.