CLIP - Contrastive Language-Image Pre-Training
OpenAI's model that understands images from natural language.
When to use CLIP
Use when:
- Zero-shot image classification (no training data needed)
- Image-text similarity/matching
- Semantic image search
- Content moderation (detect NSFW, violence)
- Visual question answering
- Cross-modal retrieval (image→text, text→image)
Metrics:
- 25,300+ GitHub stars
- Trained on 400M image-text pairs
- Matches ResNet-50 on ImageNet (zero-shot)
- MIT License
Use alternatives instead:
- BLIP-2: Better captioning
- LLaVA: Vision-language chat
- Segment Anything: Image segmentation
Quick start
Installation
Zero-shot classification
Available models
Image-text similarity
Semantic image search
Content moderation
Batch processing
Integration with vector databases
Best practices
- Use ViT-B/32 for most cases - Good balance
- Normalize embeddings - Required for cosine similarity
- Batch processing - More efficient
- Cache embeddings - Expensive to recompute
- Use descriptive labels - Better zero-shot performance
- GPU recommended - 10-50× faster
- Preprocess images - Use provided preprocess function
Performance
Limitations
- Not for fine-grained tasks - Best for broad categories
- Requires descriptive text - Vague labels perform poorly
- Biased on web data - May have dataset biases
- No bounding boxes - Whole image only
- Limited spatial understanding - Position/counting weak
Resources
- GitHub: https://github.com/openai/CLIP ⭐ 25,300+
- Paper: https://arxiv.org/abs/2103.00020
- Colab: https://colab.research.google.com/github/openai/clip/
- License: MIT


