The Most Comprehensive
Online IQ Test.

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, one of the most widely accepted frameworks for human cognitive abilities in modern psychometrics.

Yes. ACIS is a self-administered online IQ test with 20 subtests, adult norms, IQ and domain scores, and detailed score reporting. It is intended for personal insight and structured cognitive self-understanding, not official clinical, legal, employment, or high-IQ society decisions.

Free online IQ tests often use short item sets, unclear norms, or a single score. ACIS is a paid online IQ test because it includes timed subtests, adult norms, domain, index, and subtest reporting, percentile context, and tiered reports. It is still a self-administered assessment for personal insight, not an official clinical test.

Yes, for its intended use as a self-administered adult cognitive assessment. ACIS is not a licensed, proctored clinical instrument, but it is built around psychometric best practices, interpreted within an adult English-speaking reference frame of 3,243 eligible records, and refined through factor-analytic review. Current technical tables use N = 2,750 complete records and report omega, SEM, g-loading, and CFA evidence in the public technical manual.

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.

Yes, within the limits of a self-administered online assessment. ACIS is a 20-subtest cognitive assessment built for careful online measurement and adult self-understanding. It provides structured score reporting across six broad domains, while the public technical manual reports g-loading, reliability, SEM, and internal-structure evidence. The primary difference from traditional assessments is the administration format: ACIS is self-administered online and is best used for personal insight, educational planning, and structured cognitive self-understanding, while many official pathways still prefer or require proctored evidence.

All ACIS assessments require a one-time payment: Quick ($15), Optimized ($30), and Full Scale ($50). 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 details and technical context, see the About and FAQ pages.

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).

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.

The complete ACIS assessment, which includes all 20 subtests, has an estimated average completion time of about 175 minutes (roughly 2 hours and 55 minutes). Quick averages about 45 minutes and Optimized averages about 110 minutes. These are average completion estimates based on the current subtest mix and stopping rules, so individual pace will vary. Your progress is automatically saved between subtests, allowing you to return and continue later.

No. Once a subtest has been started and completed, its score is final and cannot be changed. Subtests cannot be paused, resumed, or repeated after interruption, so begin each subtest only when you have enough uninterrupted time and are ready for your first genuine attempt to count.

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.

ACIS is not a replacement for a licensed, proctored professional IQ evaluation. It emphasizes breadth, accessibility, and structured score reporting; with 20 subtests, it provides a broader online cognitive profile than many shorter internet tests. Traditional professional assessments still offer in-person observation, clinician judgment, and official-use pathways that a self-administered online battery cannot replace. ACIS is best understood as a rigorous self-assessment tool rather than a substitute for licensed, proctored evaluation.

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.

The current ACIS Full Scale IQ is strongly g-loaded. In the public technical manual, FSIQ has g loading .958; broad composites are also highly saturated, including GAI .954, CFI .949, and GRI .949. Subtest g loadings vary by construct, with reasoning and quantitative tasks generally carrying the strongest general-factor signal.

ACIS score interpretation uses an adult English-speaking reference frame of 3,243 eligible records ages 16 to 90. Current reliability and CFA tables use N = 2,750 complete records. Statistical procedures including item analysis, reliability testing, factor analysis, security filtering, and score-distribution review are applied to keep scoring tables aligned with that adult frame.

ACIS is designed to measure IQ scores ranging from 40 to 160 on the standard scale (mean = 100, SD = 15) for Standard, Quick, and Optimized assessments. Full Scale extended norms include the retained 175-177 public band. This range spans the ACIS public classifications from Severe Impairment through Profoundly Gifted. The test includes items of varying difficulty to ensure accurate measurement across this entire range without significant floor or ceiling effects.

For the public interpretation layer behind those score bands, see What Is a Good IQ? and the IQ Score Chart.

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.

Yes, some assessment data is stored, but ACIS does not sell your personal information. 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. Clearing your browser data will remove locally stored results. For full details, see our Privacy Policy.

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.

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.

It depends on the test; many online IQ tests are not very accurate because they rely on short item sets, unclear norms, or inflated scoring. ACIS differentiates itself with 20 subtests, an adult English-speaking frame of 3,243 eligible records, structured score reporting, and openly stated technical limitations. It is best used for personal insight, educational planning, and careful interpretation rather than official clinical, employment, or membership decisions.