Here we have listed various assessments and tools that are available for free online and sources of free assessments - a library of (legally) freely available PsychoDiagnostic tools.

If you know of a tool that is missing from the list, please let us know along with the source in the comments below.

• Anxiety
• Liebowitz Social Anxiety Scale Test
• CES-D Questionnaire #Emotion #Depression
• Close Relationships Questionnaires #Meaning #Relationships #AttachmentStyle
• Compassionate Love Scale #Meaning #Support #Help #Understanding
• Depression
• Depression Test by Mental Health America #Depression #FreeAssessment
• Flourishing
• PERMA #Flourishing
• PERMA Meter #Flourishing
• The Workplace PERMA profiler #Flourishing
• Gratitude Survey #Engagement #AppreciationOfPast
• Grit
• Grit Activities Grid #Grit #Personality
• Grit - College Persistence - cognitive and non-cognitive measures #Grit #Personality
• Grit Scale by Angela Duckworth #Grit #Personality 
• 8 item version #Questionnaire #ScoringGuidelines
• 8 item version for children #Questionnaire #ScoringGuidelines
• 10 item version #FreeAssessments
• 12 item version #Questionnaire #ScoringGuidelines
• Happiness
• Approaches to Happiness #LifeSatisfaction #Happiness #OverallHappiness
• Authentic Happiness Inventory #Emotion #Happiness #OverallHappiness
• Fordyce Emotions Questionnaire #Emotion #CurrentHappiness
• General Happiness Scale #Emotion #Happiness #EnduringHappiness
• Meaning in Life Questionnaire #Meaning #Meaningfulness
• Optimism Test #Engagement #Optimism
• PANAS Questionnaire #Emotion #Affect #PositiveAndNegativeAffect
• Personality Assessment
• IPIP-NEO (original 300 item IPIP representation of NEO PI-R)
• IPIP-NEO (new 120 item version)
• Locus of Control
• Primals
• Primals Inventory #Primals
• Primals Inventory - Abridged #Primals
• Primals Inventory - Micro #Primals
• Self-Control Scale for children #SelfControl #Impulsiveness #Questionnaire #ScoringGuidelines
• Transgression Motivations Questionnaire #Engagement #Forgiveness
• Satisfaction
• Satisfaction with Life Scale #LifeSatisfaction 
• Work-Life Questionnaire #Engagement #Work-LifeSatisfaction
• Strengths
• StrengthsFinder 2.0 #Strengths #Personality
• Technical Report #FreePDFDownload
• Strengths Survey
• Brief Strengths Test #Engagement #Character #CharacterStrengths
• VIA Strength Survey for Children #Engagement #Character #CharacterStrengths
• VIA Survey of Character Strengths #Engagement #Character #CharacterStrengths
• Stress & Empathy Questionnaire #LifeSatisfaction #Empathy #Stress #OverallHealth
• Substance Use Disorder
• ASSIST by WHO (The Alcohol, Smoking and Substance Involvement Screening Test) #FreeAssessment
• Clinical Opiate Withdrawal Scale (COWS) #FreeAssessment #Withdrawal
• DAST-10 (Drug Abuse Screening Test - 10 items) #FreeAssessment
• NIDA Quick Screen and NIDA modified ASSIST #FreeAssessment
• Tobacco, Alcohol, Prescription medications, and other Substance (TAPS) Tool #FreeAssessment
• Vineland Social Maturity Scale #SocialMaturity
• Well-Being Survey #LifeSatisfaction #Well-Being

Sources - PsychoDiagnostics

• International Personality Item Pool #FreeAssessments #Personality
• Mental Health America #FreeAssessments #PsychoPathology
• Open-Source Psychometrics Project #FreeAssessments
• University of Pennsylvania - Authentic Happiness - Questionnaire Center #FreeAssessments
• YourMorals.org #FreeAssessments