If your district is switching ability tests — or you're just trying to understand the alphabet soup — the two names you'll hear most are the NGAT and the CogAT. They do a similar job (measuring reasoning ability for gifted and advanced-academic screening) but they're built by different publishers, with different design philosophies and different score scales. Here's how they actually compare.
The one-paragraph summary
The CogAT (Cognitive Abilities Test) is the long-established, widely used standard, published by Riverside Insights. The NGAT (Naglieri General Ability Tests) is a newer entrant from Multi-Health Systems (MHS), designed specifically to lean less on language and reading. Both measure verbal, quantitative, and nonverbal reasoning — but the NGAT is built so a child needs less language to demonstrate their reasoning.
Side by side
| NGAT | CogAT | |
|---|---|---|
| Full name | Naglieri General Ability Tests | Cognitive Abilities Test |
| Publisher | Multi-Health Systems (MHS) | Riverside Insights |
| What it measures | General reasoning ability | Learned reasoning & problem-solving |
| Reasoning areas | Verbal, Nonverbal, Quantitative | Verbal, Quantitative, Nonverbal |
| Language load | Low by design — picture-based items, animated instructions | Increases with grade — verbal battery is teacher-read/picture-based in early grades, word-based at older levels |
| Format | Computer-based, multiple-choice, ~30 min per test | Group-administered, K–12, online or paper |
| Main score scale | Standard score: mean 100, SD 15 | Standard Age Score (SAS): mean 100, SD 16 |
| Also reported as | Percentile rank (1–99), stanine (1–9) | Percentile rank, stanine (1–9) |
| Often described as | Newer, equity-focused, reduced-language | Established, widely used standard |
The differences that actually matter
1. Language load. This is the headline difference. The CogAT includes a verbal battery, and how much language it demands depends on the level: in the early grades the verbal items are picture-based and the directions are teacher-read, while at older levels the verbal battery becomes genuinely word-based — analogies, sentence completion, verbal classification. That's a real strength for measuring verbal reasoning, but it also means a child who is still building English vocabulary (or who simply reads less fluently for their age) can, especially as the grades climb, be held back by the language rather than their reasoning. The NGAT was designed to minimize that across the board: its items are picture-based, its instructions are animated rather than read aloud, and answers are multiple-choice. The intent is to let reasoning show through with less interference from language.
2. Who publishes them — and how scores are named. Because they come from different publishers, the score scales have different names even though they're built on the same familiar 100-is-average foundation. The NGAT reports a standard score (mean 100, SD 15). The CogAT reports a Standard Age Score (SAS) (mean 100, SD 16). Both also give you a percentile rank and a stanine (a simplified 1–9 band) — and the percentile is the most directly comparable number between the two tests.
3. Track record vs. design. The CogAT's advantage is its long history and ubiquity — decades of use and norms, and the test most prep material was written for. The NGAT's advantage is its modern, equity-driven design: districts adopting it often cite the reduced-language approach as fairer across diverse student populations. Neither is "better" in the abstract — what matters is which one your district uses.
So which should you prepare for?
Prepare for the one your district actually administers — and find that out first, because it determines the format your child should be familiar with. (For example, Fairfax County switched to the NGAT in Fall 2025, replacing the CogAT it had used for 2nd graders.)
The good news: the underlying skills are nearly identical. Both tests reward the same core reasoning — finding patterns, seeing relationships, completing sequences. So practicing the kinds of thinking both tests measure is never wasted, even if your district changes tests. What changes between the two is mostly the packaging (how items look, how instructions are given), and that's exactly what a short familiarization pass before test day is for.
Want the deeper dive on either test? Read what the NGAT is, exactly, or see how to practice without anxiety for the research-backed approach that works for both.
Reasonwell Press is an independent publisher and is not affiliated with, or endorsed by, MHS, Riverside Insights, or the tests' authors. "NGAT," "Naglieri," and "CogAT" are the property of their respective owners. This article is general information for parents, not testing advice for any specific child or district.