How rare is an IQ of 115?
An IQ of 115 is at the Above average level. Under a normal model with mean 100 and standard deviation 15, IQ 115 or above has the following estimated frequency.
Deviation score
60
Top
15.87%
Rarity
1 in 6
z-score
1
On the normal-distribution model with a mean of 100 and a standard deviation of 15, an IQ of 115 corresponds to roughly the top 15.87% (about 1 in 6 people), a deviation score of 60, and a standard score of z = 1. All four values are computed from that model rather than aggregated from test-taker data; the calculation is documented on our methodology page.
Position in the IQ distribution (mean 100, SD 15)
How the percentages are calculated
We assume a normal distribution with mean 100 and SD 15. Φ is the standard normal cumulative distribution function. Values are rounded for display.
- Standard score
- z = (115 − 100) ÷ 15 ≈ 1
- Share scoring 115 or above
- [1 − Φ((115 − 100) ÷ 15)] × 100 ≈ 15.87%
- Deviation score
- 50 + (115 − 100) ÷ 15 × 10 ≈ 60
NIST: Normal Distribution documents the distribution and its cumulative function. The mean-100, SD-15 assumption is the model used on this page, not evidence that an online test is standardized.
These frequencies describe scores at or above the stated IQ, not the number with exactly that score. Confidence intervals depend on the test and its reliability; BrainRank has not established a validated ±5-point interval.
Does 5 points matter? IQ 110 / 115 / 120 compared
| IQ | Top % | Rarity |
|---|---|---|
| IQ110 | 25.25% | 1 in 4 |
| IQ115this page | 15.87% | 1 in 6 |
| IQ120 | 9.12% | 1 in 11 |
This table compares theoretical population shares. It does not establish whether a five-point difference between two test results is meaningful; that depends on the test and its reliability.
How to interpret an IQ of 115
Use the number to understand a position on a scale, then check what the particular test measures.
- •On the mean-100, SD-15 model, IQ 115 is 15 points at or above the mean; the share scoring 115 or above is about 15.87%.
- •A single IQ number does not identify which tasks you find easy. Read it alongside the test's scope and your scores in each area.
- •Compare scores only after checking the test, reference group, and standard deviation. A BrainRank estimate is not interchangeable with a standardized assessment.
Relationship to Mensa
Mensa requires a score in the top 2% on an approved, properly administered and supervised intelligence test. Under the mean-100, SD-15 normal model, IQ 115 or above corresponds to the top 15.87%. Admission cutoffs depend on the accepted test; a BrainRank estimate or certificate cannot establish eligibility.
Source: Mensa International — IQ Test FAQs
Note: Most celebrity IQ figures seen online are estimates from unreliable sources. This page does not publish individual IQ values that cannot be verified.
Frequently asked questions
- What percentile is an IQ of 115?
- An IQ of 115 corresponds to roughly the top 15.87%, or about 1 in 6 people scoring 115 or above, assuming a normal model with mean 100 and SD 15.
- Is an IQ of 115 high? Is it impressive?
- It is at the Above average level, placing it in roughly the top 15.87%. That said, IQ measures only a small part of thinking and does not determine a person's worth or success.
- Can you join Mensa with an IQ of 115?
- Mensa requires a score in the top 2% on an approved, properly administered and supervised intelligence test. Under the mean-100, SD-15 normal model, IQ 115 or above corresponds to the top 15.87%. Admission cutoffs depend on the accepted test; a BrainRank estimate or certificate cannot establish eligibility.
- What is the deviation score for an IQ of 115?
- Converting IQ (mean 100, SD 15) to a deviation score gives about 60.
Common questions in the IQ 110–119 band
- Is an IQ of 115 good enough to be proud of?
- An IQ of 115 is above roughly 84% of people — clearly above average. It is a solid result, but it should be read with the test's scope and reliability in mind.
- Does an IQ in the 110s help with studying or work?
- On average, scores in this range correlate with faster learning of new material. But the correlation is loose: study habits, domain knowledge, and persistence typically matter more for real outcomes than a 10-point IQ difference.
- How big is the gap between 115 and 120?
- 5 points. An IQ of 120 is around the top 9.12%, versus the top 15.87% at 115. Whether this difference is meaningful depends on the particular test and its reliability.
Age and testing conditions
- •IQ is a deviation score relative to people of the same age: a score compares you with your own age group, so children's and adults' scores are not on the same footing.
- •Results from informal online tests, including the test on this site, are estimates. For medical or educational decisions, use a standardized test administered by a qualified professional.
- •Sleep deprivation, fatigue, and practice effects all move measured scores. Read any single result, high or low, with that in mind.