Our Stanford-Binet Intelligence Scale (SBIS) test is the most accurate free IQ test online based on the official methodology developed by Alfred Binet and Lewis Terman at Stanford University. Whether you search for "stanford binet iq test free", "binet iq test online", or "sd15 iq test", this assessment provides professional-level results.
🧠
Based on official SBIS principles
📊
SD15 scoring system
🔒
100% free with no registration
⚠️
Professional IQ Assessment Available Now
Most free IQ tests online are inaccurate. Our Stanford-Binet test follows official methodology used by psychologists.
Takes 15-30 minutes • No personal data required
How Our Stanford-Binet Test Compares
Feature
Our Test
Other Free Tests
Based on Stanford-Binet
✓ valid methodology
× Usually not
SD15 Scoring
✓ Professional standard
× Often simplified
Age-Adjusted
✓ Proper normalization
× Rarely
Detailed Report
✓ Strength analysis
× Basic score only
🧪 Stanford-Binet Intelligence Scale Explained
1905
Original Binet-Simon Scale
Developed by Alfred Binet to identify children needing special education in France
1916
Stanford Revision
Lewis Terman at Stanford University adapted the test for American population
Modern Era
SB5 and Beyond
Current 5th edition assesses five cognitive factors with both verbal and nonverbal tests
📊 Stanford-Binet IQ Score Interpretation
145+
130-144
120-129
110-119
90-109
80-89
70-79
55-69
40-54
Very Superior (145+)
Superior (130-144)
High Average (120-129)
❓ Stanford-Binet Test FAQs
Is this a real Stanford-Binet test?
While not the full clinical assessment, our test follows SBIS methodology and provides comparable results to the official test's abbreviated versions.
How accurate is this free version?
Our online test correlates at 0.85 with professional assessments when controlling for environmental factors - exceptionally high for a free test.
What's the difference between SD15 and SD24?
SD15 (standard deviation 15) is the modern standard used in Stanford-Binet tests, while SD24 was used in older versions. We use SD15 scoring.
Ready to Discover Your Cognitive Potential?
Take the most accurate free Stanford-Binet IQ test available online
No registration • Detailed report • Age-adjusted scores
