PHQ-9 Calculator — Patient Health Questionnaire Depression Score
The PHQ-9 (Patient Health Questionnaire-9) is the most widely used validated tool for depression screening and severity measurement in primary care. Rate each of the 9 DSM-5 depression criteria on a 0–3 scale (how often you have been bothered over the past 2 weeks). This PHQ-9 calculator instantly computes your total score (0–27) and provides the corresponding severity classification.
How the PHQ-9 Depression Screening Works
The PHQ-9 maps directly to the 9 diagnostic criteria for major depressive disorder listed in DSM-5. Respondents indicate how often each symptom has bothered them over the past 2 weeks: 0 = Not at all, 1 = Several days, 2 = More than half the days, 3 = Nearly every day. The total score is the sum of all 9 responses.
Two questions are particularly important: Q1 (anhedonia) and Q2 (depressed mood) are the core diagnostic criteria — a positive screen typically requires at least one of these to be present. Q9 (self-harm thoughts) always warrants immediate clinical attention regardless of the total score. Many primary care protocols flag any Q9 response >0 for same-day clinical follow-up.
Disclaimer: The PHQ-9 is a screening tool, not a diagnostic instrument. A PHQ-9 score does not constitute a diagnosis of depression. Please consult a qualified healthcare professional for proper evaluation and treatment.
PHQ-9 in Primary Care: Clinical Use and Validity
The PHQ-9 was validated in a landmark 2001 study by Kroenke et al. (JGIM) in 6,000 patients across 8 primary care and obstetrics clinics. It demonstrated a sensitivity of 88% and specificity of 88% for major depression at a cutoff score of 10. Subsequent meta-analyses have confirmed these properties across diverse clinical populations including postpartum women, cancer patients, cardiac patients, and adolescents.
In clinical workflow, the PHQ-9 is typically administered at initial visit and at every follow-up when treating depression. Treatment algorithms (such as the Texas Medication Algorithm) use PHQ-9 scores to guide: when to initiate antidepressant therapy (score ≥10), when to consider dose escalation (persistent score ≥10 after 4–6 weeks), and when to consider remission (score <5 for two consecutive visits).
What to Do With Your PHQ-9 Score
Your PHQ-9 score is a starting point, not a verdict. Here is what different ranges typically imply for next steps:
Score 1–4 (Minimal): Monitor with watchful waiting. Lifestyle factors such as regular exercise, consistent sleep schedule, and social engagement have strong evidence for preventing progression.
Score 5–9 (Mild): Self-guided CBT apps (Woebot, Silvercloud), structured exercise programs, or brief counseling can be effective at this level. Follow up in 4–6 weeks.
Score 10–14 (Moderate): A clinician consultation is recommended. Treatment options include in-person CBT (8–20 sessions), antidepressant medication (SSRIs first-line), or both. Response should be evaluated in 4–6 weeks.
Score 15–27 (Moderately Severe to Severe): Prompt professional evaluation is important. Combination treatment (medication + therapy) is most effective for severe depression. If you have any thoughts of self-harm, contact a crisis line or emergency services immediately.
Frequently Asked Questions
What is the PHQ-9 calculator?
The PHQ-9 calculator scores the Patient Health Questionnaire-9, a validated 9-item self-report tool that measures depression severity based on the DSM-5 diagnostic criteria for major depressive disorder. Each item is rated 0 (not at all) to 3 (nearly every day). Scores range from 0 to 27.
What do PHQ-9 scores mean?
PHQ-9 score interpretation: 1–4 = minimal depression; 5–9 = mild depression; 10–14 = moderate depression; 15–19 = moderately severe depression; 20–27 = severe depression. A score of 10 or above is commonly used as the screening threshold for major depressive disorder in primary care.
How is the PHQ-9 different from the PHQ-2?
The PHQ-2 uses only the first 2 items of the PHQ-9 (anhedonia and depressed mood) as an ultra-brief screening tool. A PHQ-2 score ≥3 triggers full PHQ-9 administration. The PHQ-9 provides severity scoring and treatment guidance; the PHQ-2 is used for initial triage only.
What should I do if I score high on the PHQ-9?
If your PHQ-9 score is 10 or above, or if you answered anything other than 0 on question 9 (thoughts of self-harm), please contact a healthcare provider promptly. Effective treatments for depression include cognitive behavioral therapy (CBT), antidepressant medication, or a combination. You do not have to manage this alone.
Is the PHQ-9 in the public domain?
Yes. The PHQ-9 was developed by Kroenke, Spitzer, and Williams and is in the public domain — it can be reproduced and used freely without permission or licensing. This makes it the most widely deployed depression screening tool globally, used in primary care, emergency settings, telepsychiatry, and app-based mental health platforms.