Comparison

FastEmbed vs sentence-transformers

No clear leader: sentence-transformers (58.9) and FastEmbed (56.9) are within the 5-point margin; treat as a tie. The attribute-by-attribute breakdown below, with a source and date on every value, is the honest way to compare them.

Machine formatsMarkdownJSONGraphQLMarkdown is open. JSON and GraphQL need a free key.
FastEmbed57
sentence-transformers59
Score
vioscaleAI score
FastEmbed57 / 100medium · 54%
sentence-transformers59 / 100medium · 54%
Pricing
Free tier
FastEmbed✓
sentence-transformers✓
Model
FastEmbedopen_source
sentence-transformersopen_source
Price level
FastEmbedfree
sentence-transformersfree
Transparent
FastEmbed–
sentence-transformers✓
Integrations
Count
FastEmbed3
sentence-transformers1
Adoption
Dependent repos
FastEmbed4
sentence-transformers5,182
Github stars
FastEmbed3,244
sentence-transformers19,174
Activity
Commits last 30d
FastEmbed71
sentence-transformers100
Release
Cadence days
FastEmbed33
sentence-transformers27
History
FastEmbed20 items
sentence-transformers20 items
License
Spdx
FastEmbedApache-2.0
sentence-transformersApache-2.0
Language
Primary
FastEmbedPython
sentence-transformersPython
Market
Availability
FastEmbed–
sentence-transformersAvailable worldwide
Content
Faq
FastEmbed3 items
sentence-transformers4 items

Capabilities

Feature-by-feature on the axes that matter for embeddings apis. “-” means undocumented, not absent.

Capabilities
Architecture model
FastEmbedOpen weights local
sentence-transformersOpen weights local
Matryoshka representation learning for dimension truncation
FastEmbed-
sentence-transformers-
Multilingual support across 100 plus languages
FastEmbed✓
sentence-transformers-
Binary and scalar quantization for memory reduction
FastEmbed✓
sentence-transformers-
Cross encoder reranker API offered
FastEmbed✓
sentence-transformers✓
Late interaction architecture colbert v2
FastEmbed✓
sentence-transformers✓
Massive context window greater than 8k tokens
FastEmbed✓
sentence-transformers-
Multi modal image and text joint embeddings
FastEmbed✓
sentence-transformers✓
Task specific prefixes query vs document instructions
FastEmbed✓
sentence-transformers-
Zero data retention training opt out enterprise
FastEmbed-
sentence-transformers-
SOC2 type ii
FastEmbed-
sentence-transformers-
Mit or apache permissive oss license
FastEmbed✓
sentence-transformers-
Pricing model
FastEmbedFree open weights
sentence-transformersFree open weights

What each one is

The product in its own terms, so the numbers below have context.

FastEmbed

FastEmbed is a Python library that generates text and image embeddings using ONNX Runtime, eliminating the need for large PyTorch dependencies. It supports various embedding models including sparse embeddings, late-interaction models, and cross-encoders, making it suitable for serverless and resource-constrained environments.

Independently observed

sentence-transformers

Python toolkit for generating semantic embeddings from text, images, audio, and video using transformer-based neural networks. Supports dense embedding models, cross-encoder rerankers for scoring and ranking, and late-interaction multi-vector models for advanced retrieval tasks.

Independently observed

Pricing

List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.

FastEmbed

Open sourceFree tier
as of verify ↗

sentence-transformers

Open sourceFree tier
as of verify ↗

Platform & deployment

Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.

Deployment
Cloud / SaaS
FastEmbed✓
sentence-transformers✗
Self-hosted
FastEmbed✓
sentence-transformers✓

Integrations

What each product connects to. Counts come from the vendor's own integration directory where one exists.

FastEmbed

3 total
  • Qdrant
  • Langchain
  • Llama Index
Independently observed

sentence-transformers

1 total
  • Hugging Face Hub
Independently observed
Still deciding?

FastEmbed or sentence-transformers: which one depends on you

A composite score cannot know your constraints. Describe them and both get re-weighted against what you actually need, with the evidence behind every position.

Free to run, no account needed to start. How the evaluation works

Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.