Prompt
Do I need to re-embed everything when I switch models?
Latest observation
Oct 10, 2026
OpenAI APIWeb search: off
Usually yes—if you switch to a different embedding model, you should re-embed your documents and queries with that same model.
Why:
- Embeddings from different models live in different vector spaces.
- A vector produced by Model A is generally not comparable to one produced by Model B.
- If you mix them, similarity search results can become unreliable or meaningless.
When you can avoid re-embedding:
- If you switch to a new version of the same embedding model that is explicitly backward-compatible.
- If the vectors are only being used internally for something unrelated to semantic comparison.
- If you keep the old index and only use the new model for new documents, but then you’ll have separate indexes or you’ll need a migration plan.
Best practice:
- Re-embed all stored content when changing embedding models.
- Also re-embed any cached query embeddings.
- Rebuild or re-index your vector database with the new vectors.
If you want, I can help you figure out whether your specific model change requires a full re-embed.