Project AURIONAI Use-Cases Research & Innovation
Allen AI
language encoderfamily

Longformer

Transformer with sliding-window plus global attention that scales linearly with length, for documents of thousands of tokens; LED is its encoder-decoder for long summarisation.

Allen AIAllen AIUSA
Figure from the Longformer paper: the sliding window attention pattern.
Levelfamily
Classlanguage encoder
Parametersnot in the notes
Contextnot in the notes
Released10 Apr 2020
Opennessopen weights permissive
Runs onnot in the notes
Statusactive

Lineage

Allen AILED base 16384 belongs to this familyLLM
Allen AILongformer base 4096 belongs to this familylanguage encoder
Where this comes from
Parent and child relations from model cards, Hugging Face base_model fields and the genealogy tables of the research notes. Confidence and evidence are the notes' own.

R&D Topics

Efficiency architectures (MoE, sparse attention, long context)produced by

Identity

Developer
Allen AI
Family
not in the notes
Released
10 Apr 2020 sourcesannouncement page
Weights published
–
Record checked
12 Oct 2026
Where this comes from
Developer and dates from the research notes. Release date is the vendor's public announcement; weights date is when open weights were published.

Architecture and Size

Architecture
dense transformer
Total parameters
– sources
Active parameters
–
Checkpoint parameters
–
Context length
not in the notes
Input
text
Output
text
Where this comes from
Parameter counts as the developer states them. Where the checkpoint holds a different total, both are shown (register A16).

Openness and Access

Openness
open weights permissive
Licence
Apache License 2.0 sources
Access routes
open weights download
Where this comes from
The licence file governs over registry tags and aggregator labels.

Deployment

Runs on
not in the notes
Footprint
not in the notes
Runtimes
not in the notes
Where this comes from
Deployment tiers and runtimes as named in the notes. Footprint is the notes' figure, not a measurement by AURION.

Indonesia

Indonesian support
not stated
Regional languages
not in the notes
Jakarta hosting
unknown
Languages
Model card languages: en
Where this comes from
Indonesia fields are carried on every model; unknown is an allowed value.

Benchmark Results

The notes record no benchmark result for this model.

Industry Use Cases

No industry use case links this model.

Sources

  1. arxiv.org/abs/2004.05150 https://arxiv.org/abs/2004.05150
  2. github.com/allenai/longformer https://github.com/allenai/longformer
  3. paperswithcode.com/method/longformer https://paperswithcode.com/method/longformer
  4. github.com/tensorflow/models/tree/master/official/projec... https://github.com/tensorflow/models/tree/master/official/projects/longformer
  5. huggingface.co/allenai/longformer-base-4096 https://huggingface.co/allenai/longformer-base-4096
  6. huggingface.co/allenai/led-base-16384 https://huggingface.co/allenai/led-base-16384

To cite this page: Project AURION, AI Use-Cases Research & Innovation, "Longformer", https://aurion.semai.id/models/allen-ai-longformer/, records of October 2026.