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The Advanced Comprehensive Intelligence Scale (ACIS) is a high-range cognitive assessment tool designed to measure general intelligence (g) through 20 distinct subtests. It is built on the Cattell-Horn-Carroll (CHC) theory of cognitive abilities, the most widely accepted and empirically validated model of human cognitive abilities in modern psychometrics.

ACIS is a comprehensive cognitive evaluation built around psychometric best practices. It includes 20 subtests measuring six broad cognitive domains, adult norms based on 2,278 participants, and internal composite reliability estimates that currently range from .94 to .99 depending on the tier and index. The primary difference from traditional assessments is the administration format: ACIS is self-administered online and is intended for educational planning, cognitive self-understanding, and careful interpretation, while many official clinical or membership pathways still prefer proctored evidence.

All ACIS assessments require a one-time payment: Quick ($10), Optimized ($25), and Full Scale ($40). Our mission is to provide high-quality cognitive testing at accessible prices. All results, detailed reports, and comprehensive insights are provided without hidden fees for any assessment tier you complete.

You can contact Structural via Reddit (u/407-proxy-MR). For methodology and validation context, start with the About and Are Online IQ Tests Accurate? pages.

ACIS was created by Structural with the mission of making serious cognitive self-assessment more accessible than traditional in-person testing. Traditional professional IQ tests often cost hundreds of dollars and require professional administration. ACIS was developed to provide broader online cognitive profiling, adult norms, and transparent technical communication for users seeking careful self-understanding.

ACIS is designed and normed for adults aged 16 to 90. The test content, timing expectations, and normative comparisons are calibrated for that age range. Individuals younger than 16 or older than 90 should not use ACIS norms, because the current normative tables do not provide accurate age-based comparisons outside ages 16 to 90.

ACIS results can be used for educational planning (identifying learning strengths and areas for development), career guidance (understanding which cognitive abilities align with different professions), cognitive self-understanding (gaining insight into your thinking patterns and mental processes), and personal development (targeting specific cognitive domains for improvement). However, for official purposes like high-IQ society membership or disability accommodations, proctored testing by a licensed professional is typically required.

Currently, ACIS is only available in English. Non-native English speakers may find that their Verbal Comprehension (VCI) scores underestimate their true ability. For these individuals, the Culture-Fair Index (CFI) provides a more accurate measure of cognitive ability as it excludes verbally-loaded subtests. Future versions may include additional language options.

ACIS has been normed on a sample of 2,278 participants and refined through factor-analytic review. It was designed to reduce construct-irrelevant bias, and the public technical report with finalized g-loading and external-validity statistics is in preparation.

The Cattell-Horn-Carroll (CHC) theory is the most comprehensive and empirically supported framework for understanding human cognitive abilities. It organizes intelligence into three strata: narrow abilities (specific skills), broad abilities (like fluid reasoning and crystallized intelligence), and general intelligence (g). ACIS measures six primary broad abilities: Verbal Comprehension (Gc), Fluid Reasoning (Gf), Visual-Spatial Processing (Gv), Working Memory (Gwm), Processing Speed (Gs), and Quantitative Reasoning (Gq).

The g-loading refers to how strongly a battery measures general intelligence. ACIS was designed to achieve strong g saturation across its subtests, but the finalized public coefficient will be released in the technical documentation once validation reporting is complete.

ACIS norms were established through a rigorous norming study with 2,278 participants. The normative sample was carefully analyzed to ensure appropriate representation. Statistical procedures including item analysis, reliability testing, and factor analysis were applied to calibrate scoring tables. The norms are continuously refined as more data is collected to improve accuracy and representativeness.

The ACIS Full Scale Assessment emphasizes breadth and structured score reporting. With 20 subtests, it provides a broader online cognitive profile than many shorter internet tests. Traditional professional assessments still offer clinician observation, judgment, and official-use pathways that many institutions continue to prefer or require.

Many online IQ tests rely on short item sets, unclear norms, or inflated scoring. ACIS differentiates itself with 20 subtests, adult norms based on 2,278 participants, structured score reporting, and openly stated technical limitations. It is best used for personal insight, educational planning, research-oriented interpretation, and other settings where self-administered online measurement is acceptable. For a deeper breakdown of what makes an online test more or less trustworthy, see Are Online IQ Tests Accurate?.

Quick Assessment includes 6 core subtests measuring Verbal Comprehension (VCI), Fluid Reasoning (FRI), and Working Memory (WMI), with an estimated average completion time of about 45 minutes. Optimized Assessment includes 13 subtests covering Verbal Comprehension, Fluid Reasoning, Visual-Spatial Processing, Working Memory, and Processing Speed, and averages about 100 minutes. Full Scale Assessment includes all 20 subtests across all six cognitive domains and averages about 165 minutes. These are average completion estimates based on the current subtest mix and stopping rules, not minimum or maximum session lengths. The Full assessment provides the broadest coverage and access to all composite indices. Final reliability coefficients will be published after validation is finalized.

Choose Quick if you want a fast estimate of your cognitive abilities or are testing ACIS for the first time. Choose Optimized for a balanced profile that covers all major domains without the full time commitment - this is the recommended option for most users. Choose Full Scale if you want the broadest profile, the deepest score breakdown, and access to secondary composite indices like Culture-Fair Index (CFI), General Ability Index (GAI), and Scholastic Ability Index (SAI).

No. Each assessment tier (Quick, Optimized, Full) is a separate purchase. If you complete a Quick assessment and later want the Full Scale profile, you must use the "Clear All Data" button in the dashboard, which will erase all your previous results, and then purchase the Full assessment to start fresh. Your scores from the Quick assessment cannot be transferred or integrated into a Full assessment.

Quick measures three domains: Verbal Comprehension (VCI), Fluid Reasoning (FRI), and Working Memory (WMI). Optimized adds Visual-Spatial (VSI) and Processing Speed (PSI) for five-domain coverage plus Culture-Fair Index and General Ability Index. Full Scale measures all six domains including Quantitative Reasoning (QRI), plus provides access to 12 additional secondary composite indices for the most detailed cognitive profiling available.

The Full-Scale IQ (FSIQ) is a composite score derived from the sum of scaled scores across all subtests. It is standardized with a mean of 100 and a standard deviation of 15, allowing for direct comparison with other major standardized intelligence scales.

Verbal Comprehension (VCI) measures crystallized intelligence - your accumulated knowledge and verbal reasoning. Fluid Reasoning (FRI) assesses your ability to solve novel problems without relying on prior knowledge. Visual-Spatial (VSI) evaluates spatial reasoning and mental manipulation of visual information. Working Memory (WMI) measures your capacity to hold and process information in conscious awareness. Processing Speed (PSI) assesses how quickly you can process simple visual information. Quantitative Reasoning (QRI) measures mathematical reasoning and numerical problem-solving abilities.

A scaled score is a standardized score that allows comparison across different subtests. In ACIS, scaled scores have a mean of 10 and a standard deviation of 3. A scaled score of 10 represents exactly average performance, while scores of 7 or 13 represent performance one standard deviation below or above average, respectively. This standardization makes it possible to compare your performance across subtests that have different raw score ranges.

ACIS is designed to measure IQ scores ranging from 40 to 160 on the standard scale (mean = 100, SD = 15). Full Scale extended norms reach 175; Quick and Optimized remain within the 160 ceiling. This range covers from significantly below average to highly gifted levels of cognitive ability. The test includes items of varying difficulty to ensure accurate measurement across this entire range without significant floor or ceiling effects.

The complete ACIS assessment, which includes all 20 subtests, has an estimated average completion time of about 165 minutes (roughly 2 hours and 45 minutes). For comparison, Quick averages about 45 minutes and Optimized averages about 100 minutes. These are average completion estimates based on the current subtest mix and stopping rules, so individual pace will vary. You do not need to complete the Full assessment in one sitting, because your progress is automatically saved.

No. Once a subtest is completed, your score is final and cannot be changed. This policy exists to maintain test integrity and prevent practice effects from artificially inflating scores. For this reason, it is crucial that you only begin a subtest when you are fully prepared, well-rested, and in an optimal testing environment. Your first genuine attempt is the only attempt that counts.

Multiple subtests are necessary for comprehensive cognitive assessment. Each subtest measures different narrow abilities that contribute to broader cognitive domains. Having multiple measures per domain increases reliability and allows for a more nuanced understanding of your cognitive profile. The 20-subtest structure ensures that the FSIQ is based on a robust sampling of your cognitive abilities across all major domains.

Time limits serve different purposes depending on the subtest. For Processing Speed subtests (Coding, Symbol Search), time limits are essential as they directly measure how quickly you process information. For other timed subtests, limits prevent excessive rumination and ensure scores reflect spontaneous problem-solving ability rather than unlimited deliberation. Untimed performance on fluid reasoning tasks, for example, would measure persistence rather than cognitive ability.

Several factors can influence your performance: fatigue, sleep deprivation, stress, distractions, illness, and medication can all lower scores. Test anxiety may also impact performance, particularly on timed subtests. For the most accurate results, take ACIS when you are well-rested, alert, and in a quiet environment free from interruptions. Avoid caffeine crashes and ensure you have stable internet connectivity.

ACIS is compatible with desktop computers, laptops, tablets, and modern smartphones. For the best experience on visual and timed subtests, a larger screen, stable internet connection, and quiet environment are still recommended. A physical keyboard can be helpful for tasks like Coding, and headphones are recommended for audio-based subtests like Digit Span.

For optimal performance: get a full night's sleep before testing, avoid alcohol and heavy meals, find a quiet and comfortable environment, ensure stable internet connection, use a device with a large screen and physical keyboard, have pen and paper ready for calculations (for non-Processing Speed subtests), turn off notifications and close unnecessary applications. Unlike knowledge-based tests, you cannot "study" for an IQ test - the goal is to measure your natural cognitive ability.

ACIS works best on modern browsers including Google Chrome, Mozilla Firefox, Microsoft Edge, and Safari. Make sure your browser is updated to the latest version. Older browsers or those with strict security settings may have issues with localStorage or JavaScript features required by the test. Disable browser extensions that might interfere with website functionality during testing.

If you are interrupted during a subtest, your score for that subtest may not accurately reflect your ability, and unfortunately, you cannot retake or resume the subtest. Once started, subtests cannot be paused, and once completed, scores are final. For this reason, it is absolutely essential that you ensure an uninterrupted testing environment before beginning any subtest. Close all notifications, inform others not to disturb you, and allocate sufficient time to complete the subtest without interruption.

While you can technically retake ACIS, doing so introduces practice effects that can inflate your scores by 3-7 IQ points on average. Your first genuine attempt typically provides the most accurate measure of your cognitive ability. If you do retake, wait at least 6-12 months between attempts to minimize practice effects. Some subtests (particularly novel problem-solving tasks like Matrix Reasoning) are more susceptible to practice effects than others (like Vocabulary).

Your test progress and results are stored locally in your browser using localStorage. Additionally, when cloud sync is enabled, limited assessment data (anonymous ID, demographic info, scores, and integrity signals) may be transmitted to our secure backend (Supabase) to support test integrity and improve norms. We do not sell or share your personal information. Clearing your browser data will remove locally stored results. For full details, see our Privacy Policy.

No. High-IQ societies require scores from approved, proctored assessments administered by qualified professionals. ACIS is a self-administered online test and therefore cannot be used for official membership applications. However, ACIS can give you a reliable indication of whether pursuing official testing might be worthwhile.

Since ACIS stores your results locally in your browser's localStorage, clearing your browser data will permanently delete all your test results and progress. There is no way to recover this data once deleted. If you want to preserve your results, consider taking screenshots of your dashboard or making note of your scores before clearing browser data.

< 40: Profound Impairment. 40-54: Severe Impairment. 55-69: Mild Impairment. 70-79: Borderline. 80-89: Low Average. 90-109: Average (about 50% of the population). 110-119: High Average. 120-129: Superior. 130-134: Moderately Gifted. 135-144: Highly Gifted. 145-159: Exceptionally Gifted. 160-174: Profoundly Gifted. 175-177: Profoundly Gifted. These classifications follow the ACIS standards. For a cleaner reference table, see the IQ Score Chart. If you want the practical interpretation behind labels like average, above average, or gifted, see What Is a Good IQ?.

A confidence interval (CI) represents the range within which your "true" score likely falls. ACIS displays 95% confidence intervals, meaning there is a 95% probability that your actual cognitive ability falls within the displayed range. For example, if your FSIQ is 115 +/- 5, your true IQ is likely between 110 and 120. Confidence intervals account for measurement error inherent in all psychological testing and provide a more honest representation of your abilities than a single point estimate.

The General Ability Index (GAI) is a composite score that excludes Working Memory and Processing Speed subtests. It provides a measure of general cognitive ability that is less influenced by cognitive efficiency factors. GAI is particularly useful for individuals who may have specific weaknesses in working memory or processing speed (such as those with ADHD or certain learning disabilities) but strong reasoning and verbal abilities. A significant difference between FSIQ and GAI can reveal important information about cognitive style.

The Culture-Fair Index (CFI) excludes Verbal Comprehension subtests, which are heavily influenced by language proficiency and cultural knowledge. CFI provides a more accurate measure of fluid intelligence for individuals who are non-native English speakers or who have had limited educational opportunities. If your CFI is significantly higher than your VCI, it suggests that your true cognitive ability may be underestimated by verbally-loaded measures.

Variation between index scores is normal and reflects the natural unevenness of cognitive abilities in most individuals. Significant discrepancies (15+ points between indices) suggest a "spiky" cognitive profile where you have relative strengths and weaknesses. This can matter for how you learn, solve problems, and pace your work. For example, high Fluid Reasoning with lower Processing Speed may mean you solve complex problems well but feel slower on timed tasks.

Percentile rank indicates the percentage of the population that scored at or below your level. For example, the 84th percentile means you scored higher than 84% of the normative sample. Key benchmarks: 50th percentile = average (IQ 100), 84th percentile = one SD above average (IQ 115), 98th percentile = two SDs above average (IQ 130, high-IQ society threshold), 99.9th percentile = three SDs above average (IQ 145). To convert a score directly, use the IQ Percentile Calculator. For a broader visual guide, see the IQ Score Chart.

IQ is relatively stable in adulthood but can change. Crystallized intelligence (verbal knowledge, learned skills) tends to remain stable or increase with age and education. Fluid intelligence (novel problem-solving) typically peaks in early adulthood and gradually declines. Practice effects can temporarily inflate scores on repeated testing. Genuine changes in cognitive function can result from education, cognitive training, health conditions, brain injury, or neurodegenerative diseases. Short-term fluctuations also occur due to factors like sleep, stress, and motivation.

Verbal Comprehension (5): Antonyms, Information, Paragraph Reading, Vocabulary, Similarities. Fluid Reasoning (5): Matrix Reasoning, Figure Weights, Logic Grid, Complex Relations, Visual Number Series. Quantitative Reasoning (2): Mathematical Achievement, Arithmetic. Visual-Spatial (3): Visual Puzzles, Block Design, Spatial Comprehension. Working Memory (3): Digit Span, Alphanumeric Sequencing, Visual Sequence. Processing Speed (2): Symbol Search, Coding.

Verbal Comprehension (VCI): Crystallized intelligence, language comprehension, vocabulary knowledge, verbal reasoning. Fluid Reasoning (FRI): Novel problem-solving, pattern recognition, inductive and deductive reasoning. Visual-Spatial (VSI): Mental rotation, spatial visualization, visual analysis and synthesis. Working Memory (WMI): Short-term memory, attention, mental manipulation of information. Processing Speed (PSI): Cognitive efficiency, visual scanning speed, psychomotor speed. Quantitative Reasoning (QRI): Numerical reasoning, mathematical problem-solving, quantitative concepts.

Within the current ACIS design, subtests such as Complex Relations, Spatial Comprehension, and Mathematical Achievement contribute strongly to broad reasoning coverage. Processing Speed subtests such as Coding and Symbol Search are more domain-specific. The full battery combines high- and moderate-saturation tasks to produce a broader estimate of overall cognitive performance, while finalized public g-loading coefficients are still being prepared.

Unlike WAIS-IV which subsumes quantitative abilities under Fluid Reasoning, ACIS follows models like the Woodcock-Johnson and Stanford-Binet that recognize Quantitative Reasoning (Gq) as a distinct broad ability. Research in CHC theory supports this separation: numerical facility and mathematical reasoning draw on a unique combination of skills beyond pure fluid intelligence. This provides more detailed diagnostic information, particularly for identifying mathematical giftedness or dyscalculia.

Poor performance on a single subtest does not necessarily indicate low intelligence. It may reflect a specific narrow ability weakness, momentary distraction, misunderstanding of instructions, or simply random measurement error. This is precisely why ACIS uses 20 subtests rather than one or two - the comprehensive approach ensures that your FSIQ is not unduly influenced by performance on any single task. Focus on your overall profile and index scores rather than any individual subtest.