Model reference · open weights

pythia

pythia is an open-weight language model from EleutherAI, listed in the AxForge catalogue. AxForge can bring it up on EU-owned hardware for you on request — with the licence handled where one is required.

LLMs EleutherAI 9 variants 3.5M downloads/mo
Request this model on EU hardware All served models Not on the shared API today — deployed on request.

About

What pythia is

The Pythia Scaling Suite is a collection of models developed to facilitate interpretability research (see paper). It contains two sets of eight models of sizes 70M, 160M, 410M, 1B, 1.4B, 2.8B, 6.9B, and 12B. For each size, there are two models: one trained on the Pile, and one trained on the Pile after the dataset has been globally deduplicated. All 8 model sizes are trained on the exact same data, in the exact same order. We also provide 154 intermediate checkpoints per model, hosted on Hugging Face as branches. The Pythia model suite was deliberately designed to promote scientific research on large language models, especially interpretability research. Despite not centering downstream performance as a design goal, we find the models <a href="#evaluations"match or exceed</a the performance of similar and same-sized models, such as those in the OPT and GPT-Neo suites. Previously, we released an early version of the Pythia suite to the public. However, we decided to retrain the model suite to address a few hyperparameter discrepancies. This model card <a href="#changelog"lists the changes</a; see appendix B in the Pythia paper for further discussion. We found no difference in benchmark performance between the two Pythia versions. The old models are still available, but we suggest the retrained suite if you are just starting to use Pythia.<br This is the current release. Please note that all models in the Pythia suite were renamed in January 2023. For clarity, a <a href="#naming-convention-and-parameter-count"table comparing the old and new names</a is provided in this model card, together with exact parameter counts. Pythia-160M Model Details - Developed by: EleutherAI - Model type: Transformer-based Language Model - Language: English - Learn more: Pythia's GitHub repository for training procedure, config files, and details on how to use. See paper for more evals and implementation details. - Library: GPT-NeoX - License: Apache 2.0 - Contact: to ask questions about this model, join the [EleutherAI Discord](https://discord.gg/zBGx3azzUn), and post them in #release-discussion. Please read the existing Pythia documentation before asking about it in the EleutherAI Di

Summarised from the published model card. Read the full card on the HuggingFace links below.

Specifications

What it is

MakerEleutherAI
TypeLanguage models
Parameters (lead)213M
Context2k tokens
Variants9
Runs withtransformers
Released2023-02-08
Popularity3.5M downloads / month
Likes146
LicenceOpen weights

How it works

How language models work

Your prompttext / messagesTransformerattention over tokensNext-token loopgenerate + streamResponsetext · tool callsA language model reads your tokens and predicts the next one, again and again, streaming the reply back.

Variants

Sizes & precisions

Open weights ship in several sizes and precisions. One page, all the variants — pick the one that fits your GPU. VRAM figures are estimates from model size.

VariantParamsPrecisionVRAMFits 16 GBWeights
pythia-160m213MBF16~0.5 GBWeights ↗
pythia-14m14MBF16~0 GBWeights ↗
pythia-410m506MBF16~1.2 GBWeights ↗
pythia-1.4b1.5BBF16~3.5 GBWeights ↗
pythia-1b1.1BBF16~2.5 GBWeights ↗
pythia-6.9b7.0BBF16~16.1 GBWeights ↗
pythia-2.8b2.9BBF16~6.7 GBWeights ↗
pythia-12b12.0BBF16~27.6 GBWeights ↗
pythia-31m30MBF16~0.1 GBWeights ↗

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys pythia for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (pythia below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/chat/completions \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"pythia","messages":[{"role":"user","content":"Hello"}]}'

Details

Languages, data & research

Languages

en

Trained / evaluated on

EleutherAI/pile EleutherAI/the_pile the_pile

Tags

transformers pytorch safetensors gpt_neox text-generation causal-lm pythia en dataset:EleutherAI/pile text-generation-inference endpoints_compatible deploy:azure dataset:EleutherAI/the_pile dataset:the_pile

Papers

Licence

Open weights

Open weights under apache-2.0 — commercial use is permitted. Deploy it on AxForge EU hardware on request. Read the licence ↗

Sources

Weights & code

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