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MedGemma 1.5 4B

MedGemma 1.5 4B is a multimodal foundation model developed by Google Research. It has a parameter scale of approximately 40.0B and supports a long context window of 128K.

Parameters

40.0B

Context Window

128K

License

Apache 2.0

Release Date

2026-01-13

API Pricing

API pricing for this model is not yet available

Strengths

  • Advanced multimodal capabilities
  • 128K long context processing capacity
  • Apache 2.0 open-source license

Weaknesses

  • 40.0B computational resource load
  • Limited specialization in specific domains
  • Lack of real-time update capability

Use Cases

  • Multimodal analysis of medical data
  • Summarization and analysis of long professional documents
  • Open-source medical AI development

Deep Analysis

Parameters

4B

Updated version of MedGemma 1 4B with expanded capabilities

Release Date

January 2026

MedGemma 1.5 update

New Capabilities

CT/MRI, WSI, longitudinal imaging

3D volume interpretation, whole-slide histopathology, longitudinal chest X-rays

Anatomical Localization

Bounding box support

Can localize anatomical features in chest X-rays

EHR Understanding

Yes

Interprets text-based Electronic Health Record data

Lab Report Extraction

Yes

Extracts structured data from unstructured medical lab reports

License

HAI-DEF Terms of Use

Health AI Developer Foundations license

Base Model

Gemma 3

With medically optimized SigLIP image encoder

Strengths

  • Expands MedGemma 1 4B with CT/MRI 3D imaging, whole-slide histopathology, and longitudinal imaging
  • Bounding box anatomical localization in chest X-rays
  • Structured data extraction from unstructured lab reports
  • EHR text interpretation capability
  • Improved accuracy on medical text reasoning vs MedGemma 1 4B
  • Runs on mobile/edge hardware

Weaknesses

  • Only available as 4B multimodal instruction-tuned variant (no larger sizes for 1.5)
  • HAI-DEF license more restrictive than Apache 2.0
  • Limited to text output (no image generation)
  • Requires fine-tuning for optimal clinical performance
  • New capabilities may have limited benchmark coverage

Competitor Comparison

ModelArenaSWEGPQAPrice
MedGemma 1.5 4BN/AN/A~67% (MedQA est)Free (open weights)
MedGemma 1 4BN/AN/A64.4% (MedQA)Free (open weights)
MedGemma 1 27BN/AN/A87.7% (MedQA)Free (open weights)
BioMistral 7BN/AN/A~60% (MedQA)Free (open weights)

MedGemma 1.5 4B is the updated version of MedGemma 1 4B, expanding medical AI capabilities to include 3D CT/MRI interpretation, whole-slide histopathology, longitudinal chest X-ray comparison, anatomical bounding box localization, and structured lab report extraction. Released January 2026.

Analysis generated: 2026-05-24