Proprietary scoring methodology

The Cognitive Performance Index

A science-backed 0–100 scoring system that evaluates nootropics across evidence quality, cognitive coverage, effect size, safety, and bioavailability. No hype — just data.

Elite Tier

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How We Score

Every compound is evaluated across five weighted categories, producing a composite CPI score from 0 to 100.

Evidence Quality

30pts30%

The rigor and reliability of the scientific research supporting cognitive benefits.

View scoring criteria

Number and quality of randomized controlled trials (RCTs)
Availability of systematic reviews and meta-analyses
Sample sizes and statistical power of key studies
Replication of findings across independent research groups
Publication in peer-reviewed, high-impact journals
Study design quality (double-blind, placebo-controlled)

Cognitive Domain Coverage

20pts20%

The breadth of cognitive functions enhanced, measured across 10 key domains.

View scoring criteria

Number of cognitive domains with demonstrated benefits
Strength of evidence within each domain
Balance across cognitive, mood, and energy domains
Specificity vs. broad-spectrum cognitive enhancement
Relevance to real-world cognitive performance tasks

Effect Size & Consistency

20pts20%

The magnitude and reliability of cognitive improvements observed in research.

View scoring criteria

Cohen's d or equivalent effect size measures
Consistency of effects across different populations
Dose-response relationship clarity
Duration of effects (acute vs. sustained)
Minimal variability in outcomes between studies

Safety & Tolerability

15pts15%

The safety profile including side effects, interactions, and long-term tolerability.

View scoring criteria

Incidence and severity of adverse effects
Long-term safety data availability
Drug interaction profile
Contraindication specificity
Regulatory status and history of safe use
Therapeutic index (distance between effective and harmful doses)

Bioavailability & Practical Usability

15pts15%

How effectively the compound is absorbed and how practical it is for daily use.

View scoring criteria

Oral bioavailability percentage
Blood-brain barrier penetration
Onset time and duration of action
Stability and shelf life
Availability of standardized formulations
Cost accessibility and supplement availability

CPI Tier System

Elite

85–100

Strong

70–84

Promising

55–69

Moderate

40–54

Emerging

25–39

Insufficient

0–24

Rankings

15 compounds ranked

Modafinil

0Elite

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	9
Working Memory	8
Long-Term Memory & Recall	6
Executive Function	9
Processing Speed	8
Verbal Fluency	7
Neuroplasticity / Learning	6
Mental Energy / Fatigue Resistance	9
Motivation / Drive	8
Mood & Stress Resilience	7

Focus9Executive Function9Mental Energy9

Prescription required in most countries

100–200mg · 30–60 minutes

Adderall

Mixed Amphetamine Salts

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	10
Working Memory	9
Long-Term Memory & Recall	4
Executive Function	9
Processing Speed	9
Verbal Fluency	6
Neuroplasticity / Learning	2
Mental Energy / Fatigue Resistance	10
Motivation / Drive	9
Mood & Stress Resilience	4

Focus10Mental Energy10Working Memory9

Schedule II controlled substance — prescription required. High dependency potential.

5–30mg · 20–45 minutes (IR), 30–60 minutes (XR)

Caffeine

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	9
Working Memory	6
Long-Term Memory & Recall	4
Executive Function	6
Processing Speed	8
Verbal Fluency	5
Neuroplasticity / Learning	3
Mental Energy / Fatigue Resistance	9
Motivation / Drive	7
Mood & Stress Resilience	5

Focus9Mental Energy9Processing Speed8

100–200mg · 15–45 minutes

Creatine

Monohydrate

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	6
Working Memory	7
Long-Term Memory & Recall	6
Executive Function	7
Processing Speed	7
Verbal Fluency	5
Neuroplasticity / Learning	6
Mental Energy / Fatigue Resistance	8
Motivation / Drive	5
Mood & Stress Resilience	6

Mental Energy8Working Memory7Executive Function7

3–5g daily · 1–2 weeks (loading)

Omega-3 DHA

Docosahexaenoic Acid

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	5
Working Memory	6
Long-Term Memory & Recall	7
Executive Function	6
Processing Speed	6
Verbal Fluency	5
Neuroplasticity / Learning	7
Mental Energy / Fatigue Resistance	5
Motivation / Drive	4
Mood & Stress Resilience	7

Long-Term Memory & Recall7Neuroplasticity7Mood & Stress Resilience7

1–2g EPA+DHA daily · 4–12 weeks

Cognizin®

Citicoline (CDP-Choline)

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	7
Working Memory	6
Long-Term Memory & Recall	7
Executive Function	6
Processing Speed	7
Verbal Fluency	5
Neuroplasticity / Learning	6
Mental Energy / Fatigue Resistance	6
Motivation / Drive	4
Mood & Stress Resilience	5

Focus7Long-Term Memory & Recall7Processing Speed7

250–500mg · 1–2 hours (acute); 2–4 weeks (full cognitive benefits)

L-Theanine

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	8
Working Memory	6
Long-Term Memory & Recall	4
Executive Function	6
Processing Speed	5
Verbal Fluency	5
Neuroplasticity / Learning	4
Mental Energy / Fatigue Resistance	6
Motivation / Drive	5
Mood & Stress Resilience	8

Focus8Mood & Stress Resilience8Working Memory6

100–200mg · 30–60 minutes

Bacopa Monnieri

BacoMind / Synapsa

0Strong

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	7
Working Memory	7
Long-Term Memory & Recall	9
Executive Function	6
Processing Speed	6
Verbal Fluency	6
Neuroplasticity / Learning	8
Mental Energy / Fatigue Resistance	4
Motivation / Drive	3
Mood & Stress Resilience	6

Long-Term Memory & Recall9Neuroplasticity8Focus7

300–600mg (standardized) · 4–12 weeks

Alpha-GPC

0Promising

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	7
Working Memory	7
Long-Term Memory & Recall	8
Executive Function	5
Processing Speed	5
Verbal Fluency	6
Neuroplasticity / Learning	7
Mental Energy / Fatigue Resistance	5
Motivation / Drive	4
Mood & Stress Resilience	4

Long-Term Memory & Recall8Focus7Working Memory7

300–600mg · 30–60 minutes

#10

Rhodiola Rosea

SHR-5 Extract

0Promising

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	6
Working Memory	5
Long-Term Memory & Recall	5
Executive Function	5
Processing Speed	5
Verbal Fluency	4
Neuroplasticity / Learning	5
Mental Energy / Fatigue Resistance	8
Motivation / Drive	7
Mood & Stress Resilience	8

Mental Energy8Mood & Stress Resilience8Motivation7

200–600mg · 30–60 minutes

#11

Ashwagandha

KSM-66

0Promising

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	5
Working Memory	5
Long-Term Memory & Recall	5
Executive Function	5
Processing Speed	5
Verbal Fluency	4
Neuroplasticity / Learning	5
Mental Energy / Fatigue Resistance	7
Motivation / Drive	6
Mood & Stress Resilience	9

Mood & Stress Resilience9Mental Energy7Motivation6

300–600mg (KSM-66) · 2–4 weeks

#12

Lion's Mane

Hericium erinaceus

0Promising

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	5
Working Memory	5
Long-Term Memory & Recall	7
Executive Function	4
Processing Speed	4
Verbal Fluency	4
Neuroplasticity / Learning	9
Mental Energy / Fatigue Resistance	4
Motivation / Drive	4
Mood & Stress Resilience	7

Neuroplasticity9Long-Term Memory & Recall7Mood & Stress Resilience7

500mg–3g daily · 2–4 weeks

#13

Theacrine

TeaCrine®

0Promising

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	6
Working Memory	4
Long-Term Memory & Recall	3
Executive Function	4
Processing Speed	5
Verbal Fluency	3
Neuroplasticity / Learning	2
Mental Energy / Fatigue Resistance	7
Motivation / Drive	6
Mood & Stress Resilience	6

Mental Energy7Focus6Motivation6

100–300mg · 30–60 minutes

#14

Nicotine

Patch / Gum (low-dose)

0Promising

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	8
Working Memory	7
Long-Term Memory & Recall	5
Executive Function	6
Processing Speed	8
Verbal Fluency	5
Neuroplasticity / Learning	4
Mental Energy / Fatigue Resistance	7
Motivation / Drive	6
Mood & Stress Resilience	4

Focus8Processing Speed8Working Memory7

High addiction potential — not recommended for regular use

1–2mg (patch/gum) · 5–15 minutes

#15

Dynamine™

Methylliberine

0Moderate

Cognitive domain scores
Domain	Score (0-10)
Focus / Sustained Attention	5
Working Memory	3
Long-Term Memory & Recall	2
Executive Function	3
Processing Speed	4
Verbal Fluency	2
Neuroplasticity / Learning	2
Mental Energy / Fatigue Resistance	6
Motivation / Drive	5
Mood & Stress Resilience	4

Mental Energy6Focus5Motivation5

Limited long-term human data — cycle use and avoid daily chronic dosing

100–200mg · 15–30 minutes

Built for Clarity

The Cognitive Performance Index is an evolving, open methodology. As new research is published and replicated, scores are updated to reflect the latest scientific consensus. Our goal is to cut through the noise and give you an honest, evidence-weighted view of what works.

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Disclaimer: CPI scores are for informational and educational purposes only. They do not constitute medical advice. Always consult a qualified healthcare professional before starting any supplement regimen. Individual responses to nootropics vary significantly.