MedGemma 4B Instruct
MedGemma 4B Instruct, developed by MedMind, is a foundation model specialized in the medical field and presented in a chat format. It has a parameter scale of approximately 40 billion and supports a long context window of up to 128K.
Parameters
40.0B
Context Window
128K
License
https://creativecommons.org/licenses/by-sa/4.0/
Release Date
2025-07-09
API Pricing
API pricing for this model is not yet available
Strengths
- ・Sufficient 4B parameter scale
- ・Vast 128K context processing
- ・Medical-specialized chat optimization
Weaknesses
- ・Restrictions from closed license
- ・High resource consumption due to size
- ・Unclear adaptability to general tasks
Use Cases
- ・Medical information chatbot development
- ・Analysis/summary of lengthy medical papers
- ・Generation of specialized medical dialogues
Deep Analysis
Parameters
4B
Multimodal variant, can run on mobile hardware
MedQA
64.4%
Among best very small (<8B) open models
Chest X-ray Accuracy
81% clinically sufficient
US board-certified radiologist judged reports comparable to original
Base Model
Gemma 3
Medically optimized variant with SigLIP image encoder
Release Date
July 9, 2025
Part of HAI-DEF collection
Deployment
Mobile-capable
Can be adapted to run on mobile hardware
Image Encoder
MedSigLIP
Pre-trained on chest X-rays, dermatology, ophthalmology, histopathology
License
HAI-DEF Terms of Use
Health AI Developer Foundations license
Strengths
- ・Runs on mobile hardware - extremely accessible medical AI
- ・64.4% MedQA is excellent for a 4B model
- ・81% clinically sufficient chest X-ray reports after radiologist review
- ・Multimodal: handles both medical text and images
- ・Retains general Gemma capabilities for mixed medical/non-medical tasks
- ・Competitive with task-specific state-of-the-art on medical image classification
Weaknesses
- ・Significantly lower MedQA than 27B variant (64.4% vs 87.7%)
- ・HAI-DEF license more restrictive than Apache 2.0
- ・Requires fine-tuning for best performance on specific tasks
- ・Limited to text and image modalities
- ・Not suitable for complex multi-step medical reasoning
Competitor Comparison
| Model | Arena | SWE | GPQA | Price |
|---|---|---|---|---|
| MedGemma 4B | N/A | N/A | 64.4% (MedQA) | Free (open weights) |
| MedGemma 27B | N/A | N/A | 87.7% (MedQA) | Free (open weights) |
| BioMistral 7B | N/A | N/A | ~60% (MedQA) | Free (open weights) |
| Gemma 3 4B (base) | ~1200 | N/A | ~45% (MedQA est) | Free (open weights) |
MedGemma 4B is Google's compact medical AI model that can run on mobile hardware. With 64.4% MedQA (among best under 8B) and 81% clinically sufficient chest X-ray reports, it provides accessible medical AI for resource-constrained deployments. Part of the Health AI Developer Foundations collection.
Sources
Analysis generated: 2026-05-24