uvloop

Ultra fast asyncio event loop for Python.

EstablishedOpen SourceLow lock-in

Pricing

Free tier

Flat rate

Adoption

Stable

License

Open Source

Data freshness

Aging · Jun 8, 2026

Overview

What is uvloop?

uvloop is an ultra-fast drop-in replacement for the built-in asyncio event loop. It leverages the high-performance libuv library to provide significant speed improvements over the default asyncio implementation, making it ideal for high-throughput and low-latency applications.

Key differentiator

uvloop stands out as an ultra-fast, drop-in replacement for the default asyncio event loop, offering significant speed improvements without requiring substantial code changes.

Capability profile

Capability Radar

Ease of StartEcosystemValueMaturityFlexibilityScale Ready

Honest assessment

Strengths & Weaknesses

↑ Strengths

Significantly faster than the default asyncio event loop.medium

Drop-in replacement for asyncio, minimal code changes required.medium

Built on top of libuv for high performance.medium

Supports all features of the standard asyncio library.medium

↓ Weaknesses

Limited compatibility with certain asyncio featureshigh

Some advanced asyncio features may not be fully supported or behave differently compared to the default event loop.

Dependency on libuv can introduce platform-specific issuesmedium

libuv's performance and behavior can vary across different operating systems, leading to potential instability or reduced performance on certain platforms.

Requires Python 3.7+ which may not be feasible for all projectslow

Projects still using older versions of Python cannot benefit from uvloop's performance improvements without upgrading their environment.

Fit analysis

Who is it for?

✓ Best for

Developers building high-throughput, low-latency Python applications using asyncio.

Teams working on real-time systems where performance is critical.

Projects requiring significant improvements in event loop speed over the default asyncio implementation.

✕ Not a fit for

Applications that do not require high-performance event loops and can function well with the standard asyncio library.

Scenarios where the overhead of integrating a new event loop outweighs potential performance gains.

Cost structure

Pricing

Free Tier

Available

Open source — free to use

Starts at

$0

Model

Flat rate

Enterprise

None

Performance benchmarks

How Fast Is It?

Ecosystem

Relationships

Next step

Get Started with uvloop

Step-by-step setup guide with code examples and common gotchas.

View Setup Guide →