Differential Diagnosis Generators: Top Tools & Recommendations

Differential diagnosis (DDx) generators help clinicians, students, or patients input symptoms, labs, or findings to produce prioritized lists of possible conditions. I've focused on the most relevant, up-to-date options (as of 2026) from AI-powered web tools to established apps. These range from free consumer-facing options to professional-grade platforms. Key categories: AI-driven (fast, evidence-based), symptom/lab-focused apps, and image/visual aids.

Comparison Table

Detailed Recommendations

Best Free Option: DxGPT

• Enter symptoms in natural language (e.g., "45yo male with fever, cough, fatigue").
• AI (GPT-5 mini) analyzes patterns for a ranked DDx list with rationale, tests, and refinements.
• Choose if: You're testing ideas quickly or need patient-friendly access. Fully free and secure.

Best Pro AI Tool: Glass Health

• Handles nuanced cases (e.g., amyloidosis DDx with age/sex/history).
• Integrates scribing, drug info, and cited guidelines.
• Choose if: You're a clinician wanting end-to-end support (dx + docs). Start free, scales to paid.

Best for Visual/Established: VisualDx

• Builds DDx via symptom search + photo uploads for matches.
• Strong in clinics/hospitals for equity/rural care.
• Choose if: Dermatology, rashes, or image-based reasoning is key. Institutional pricing common.

Budget App Pick: STATworkUP DDx

• Relational DB correlates 1000s of symptoms/labs; adjusts probabilities.
• Offline, no internet needed post-download.
• Choose if: You want a one-time buy for mobile reliability.

Honorable Mentions:

• Diagnosaurus DDx (App/AccessMedicine): Free web access for symptom browses; quick but basic.
• Symptomate (symptomate.com): Free symptom checker for triage/DDx basics (patient-oriented).
• Avoid consumer apps like Ada/Buoy for pro use—they're triage, not deep DDx.

How to Choose

• Free & Casual/Student: DxGPT or DDxHub.
• Clinician/Point-of-Care: Glass Health or Isabel (if budget allows).
• Offline/Mobile: STATworkUP.
• Specialty: VisualDx (visuals), DDxHub (labs/rare). All emphasize: Not substitutes for judgment—use as support. AI tools excel in speed/bias reduction but need validation.

What specifics can you share (e.g., physician/student/patient, specialty like derm/internal med, free/paid preference, web/app)? Or symptoms for a demo recommendation?

Differential diagnosis (DDx) generators have evolved from simple digital checklists into sophisticated, AI-driven platforms that integrate directly into clinical workflows.

The following tools are the current industry leaders, categorized by their primary strength:

1. The "Gold Standard" Checklist: Isabel Pro

Isabel is widely considered the most powerful and validated DDx generator. It uses natural language processing to take patient symptoms (free text) and instantly generate a list of possibilities.

• Best For: Clinicians and students who need a comprehensive "don't-miss" list.
• Pros: Flags "Red Flag" (life-threatening) conditions; integrates with many Hospital Systems (EHR); covers 10,000+ conditions.
• Cons: Requires a subscription (often provided by hospitals or medical schools).
• Comparison: Unlike search engines, it won't give you just one answer; it forces you to look at the "zebras" you might have missed.

2. Best for Visual Cases (Dermatology/Eyes): VisualDx

If your differential involves a skin condition, rash, or ocular finding, VisualDx is the superior choice. It features the world’s largest curated medical image library.

• Best For: Primary care, ER, and dermatology.
• Pros: High accuracy for diverse skin tones; allows you to build a differential by selecting morphology (e.g., "annular macule"); contains excellent patient education handouts.
• Cons: Expensive for individual users; very specialized toward visual findings.

3. Best for Point-of-Care Speed: BMJ Best Practice

BMJ Best Practice is designed for the "busy resident" workflow. Each disease module has a dedicated "Differential Diagnosis" tab that displays a clean, structured table.

• Best For: Quick orientation during rounds or in the clinic.
• Pros: Categorizes conditions into "Common" vs. "Uncommon"; provides a step-by-step investigation plan for each.
• Cons: Not as "exploratory" as Isabel; you usually have to have a starting diagnosis in mind to find the table.

4. Best AI-Powered Reasoning: Glass Health

A newer entrant, Glass Health uses large language models (LLMs) to not just list diagnoses, but to help you write your "Assessment and Plan."

• Best For: Medical students and residents practicing clinical reasoning.
• Pros: Explains the why behind its suggestions; creates structured clinical notes; offers a free tier for a limited number of queries.
• Cons: Like all LLMs, it requires human verification to avoid "hallucinations" of rare syndromes.

5. Best Free/Open Access Alternatives

• DxGPT: A non-profit AI tool developed by Foundation 29. It is specifically designed to help with rare diseases and complex cases for free.
• River Editor: A simple, free web tool that generates a ranked DDx list with supporting and opposing reasoning for each condition.
• DynaMed (integrated Isabel): If your institution pays for DynaMed, you often have a "DDx" button that opens an Isabel-powered generator at no extra cost.

Comparison Summary

How to Choose:

• Are you a medical student? Start with Glass Health or BMJ Best Practice to help structure your clinical notes and learn the "classic" presentations.
• Are you an ER or Primary Care doctor? Isabel Pro is the best "safety net" to ensure you aren't missing a life-threatening "don't-miss" diagnosis.
• Stumped by a rash? Use VisualDx immediately.

Are you looking for a tool for personal use (as a student) or for institutional integration into an EHR? Also, do you prefer a tool that asks you questions (step-by-step) or one where you paste a whole patient history?