PyRank
Dao-AILab

flash-attn

Fast and memory-efficient exact attention
PyPI GitHub
No known security advisories. The current version has no OSV.dev malware reports and no critical or high-severity vulnerabilities.

flash-attn has 552K monthly downloads and 24K GitHub stars. Version 2.8.3.post1 supports Python 3.9+, first published in 2022.

It is actively maintained under a permissive license, last released in Jun 2026.

It is built on top of einops and torch. It is used by 49 tracked packages, including openrlhf, exllamav3 and nano-vllm-voxcpm.

Shared Repository
This package shares its GitHub repository (Dao-AILab/flash-attention) with 7 other packages. Stars, forks, and other GitHub metrics reflect the entire repository.
Downloads
Day
17.4K
Week
111.8K
Month
552.4K
Stars
24.4K
Forks
2.9K
Issues
1.0K
Version
2.8.3.post1

Package Insights

What's this?
Score breakdown - each component scores 0-100, weighted by percentage
Maintenance
100
Popularity
91
Adoption
57
Community
80
Provenance
0
How the maintenance status was determined
Last commit
3 days ago
Monthly downloads
552,383
• Active
Activity within 30 days
Stable
Activity within 31-180 days
Minimal
Activity within 181-365 days, or no activity data
At Risk
No activity for > 365 days, but > 10,000 monthly downloads
Archived
Repository flagged as archived on GitHub
How the popularity category was determined
Monthly downloads
552,383
Stars
24,362
Stars per 1k downloads
44.10
Industry Standard
> 10,000,000 monthly downloads
Hidden Gem
< 0.5 stars per 1k downloads and > 100,000 monthly downloads
• Community Favorite
> 5 stars per 1k downloads
Rising Star
Balanced ratio of stars to downloads
Unknown
Fewer than 1,000 monthly downloads, or no star data
How download momentum is calculated
Week daily avg
15,972
Month daily avg
18,413
Momentum
-13.3%
((week_daily_avg - month_daily_avg) / month_daily_avg) * 100
Python version support tiers
requires_python
>=3.9
Cutting Edge
Minimum supported version is 3.12 or newer
• Modern
Minimum supported version is 3.9, 3.10, or 3.11
Legacy
Supports 3.8 or older (or Python 2)
Unknown
No requires_python specified or unparseable
License categories
License
BSD License
• Permissive
MIT, Apache, BSD, ISC, Unlicense, CC0, etc.
Copyleft
GPL, LGPL, AGPL, MPL, EPL, etc.
Proprietary
Commercial, all rights reserved, custom EULAs
Unknown
No license specified, or none of the above match
How the release cadence was determined
Last release
25 days ago
Total releases
80
Releases/year
22.0
• Rapid
Last release within 365 days and > 12 releases/year
Regular
Last release within 365 days
Slow
Last release 366-730 days ago
Stalled
Last release > 730 days ago, or no releases
Unknown
No usable release date available
How contributor risk was determined
Contributors
207
Monthly downloads
552,383
High Load
≤ 2 contributors and ≥ 50,000 monthly downloads
Moderate Load
< 10 contributors and ≥ 500,000 monthly downloads
Low Load
< 25 contributors and ≥ 5,000,000 monthly downloads, or sole maintainer with ≥ 10,000 monthly downloads
• Balanced
Enough contributors for the package's popularity
Unknown
No contributor data available
Engagement
80
 
Issue Burden
41.6
per 1k stars
Discussions
1.0
per 1k stars
Fork Ratio
7.2%
contrib / forks
Stale Release
No
 
PR Velocity
Active
 

Weekly Downloads

GitHub Stars

Not all downloads include detailed metadata. Breakdowns reflect the subset that does.

Downloads by OS

Linux 10.1K
Windows 686
macOS 137

Python Versions

3.12
44.2% 4.8K
3.10
29.6% 3.2K
3.11
14.1% 1.5K
3.13
9.7% 1.0K
3.14
2.4% 258

Top Countries

1. US US
7.8K
2. CN CN
455
3. SG SG
347
4. GB GB
342
5. HK HK
227
6. JP JP
214
7. CA CA
204
8. IT IT
198
9. ES ES
176
10. CH CH
145

Package Information

License
BSD License
First Release
November 15, 2022
Last Release
3 weeks ago
Last Commit
4 days ago
Latest Version
2.8.3.post1
Total Releases
80
Contributors
207
Open PRs
202
Archived
No
Author
Tri Dao
Python Versions
3
Tracking Since
January 6, 2026
Data Updated
July 5, 2026
Data Freshness
Fresh

Links