# ESMC-6B by Biohub: Open-Weight Model
Source: https://savrn.com/models/esmc-6b
Markdown alternate of the page above; the site index is https://savrn.com/llms.txt

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## Runs On

What it takes to serve ESMC-6B (6.4B parameters): the memory its weights need at each precision, and the cheapest way to rent enough data-center GPUs to hold them.

| Precision | Weights | Memory needed | Cheapest setup | Per hour | Also fits |
| --- | --- | --- | --- | --- | --- |
| 16-bit | 12.7 GB | 15.2 GB | 1x [MI300X](https://savrn.com/ai-index/pricing/gpus/mi300x) (192 GB) Vultr | $1.85 | [1x H100](https://savrn.com/ai-index/pricing/gpus/h100) $1.99 · [1x MI325X](https://savrn.com/ai-index/pricing/gpus/mi325x) $2.00 |
| 8-bit | 6.4 GB | 7.6 GB | 1x [MI300X](https://savrn.com/ai-index/pricing/gpus/mi300x) (192 GB) Vultr | $1.85 | [1x H100](https://savrn.com/ai-index/pricing/gpus/h100) $1.99 · [1x MI325X](https://savrn.com/ai-index/pricing/gpus/mi325x) $2.00 |
| 4-bit | 3.2 GB | 3.8 GB | 1x [MI300X](https://savrn.com/ai-index/pricing/gpus/mi300x) (192 GB) Vultr | $1.85 | [1x H100](https://savrn.com/ai-index/pricing/gpus/h100) $1.99 · [1x MI325X](https://savrn.com/ai-index/pricing/gpus/mi325x) $2.00 |

Memory is the weights at that precision plus 20% for the runtime and a short context; a long context needs more. Prices are the lowest on-demand hourly rates in the [SAVRN Index](https://savrn.com/ai-index/pricing/gpus), read Oct 24, 2026.

[ESMC-6B on every accelerator the SAVRN Index prices, at every precision](https://savrn.com/models/esmc-6b/gpus)

## SAVRN's Notes on ESMC-6B

ESMC 6B is a protein language model: it learned the patterns of protein biology from billions of sequences and turns a protein into a representation that downstream models can use for function, structure or design work. Biohub publishes it, and 2.9 million downloads a month show it is already a standard tool.

At 6.4B parameters it fits on one modern GPU at 16-bit, about 15 GB with working room. The MIT license allows commercial use, which is notable in a field where many strong models carry noncommercial terms. For therapeutic or industrial protein work, this is a foundation worth testing early.

SAVRN Research, 2026-09-18

## Model Card

By Biohub, published under mit, revision af1602ba7406.

### ESMC

### Model Details

ESMC is a state-of-the-art protein language model that has learned the rules of protein biology from training on billions of protein sequences. ESMC provides representations of proteins enabling novel AI applications from therapeutic protein engineering to unlocking basic insights into protein biology across life.

The ESMC 6B model has 6 billion parameters, with 80 layers and 2.37e23 training flops. We additionally release overtrained 300M and 600M parameter variants of ESMC for local inference and finetuning.

The [ESMFold2](https://huggingface.co/biohub/ESMFold2) structure prediction models are trained on top of a frozen ESMC 6B language model. ESMFold2 is a state-of-the-art model for protein structure prediction and design that defines a new frontier for speed and accuracy.

The [ESMC sparse autoencoder](https://huggingface.co/biohub/ESMC-6B-sae-layer60-k64-codebook16384), ESMC-6B-sae-layer60-k64-codebook16384, is built on the ESMC 6B model and provides human-interpretable, agent-generated feature descriptions. See the [ESMC SAE overview card](https://huggingface.co/biohub/ESMC-SAE-Overview) for the full set of ESMC SAE variants.

[Read the full model card (1,376 words)](https://savrn.com/models/esmc-6b/card)

## Configuration

Architecture

EsmcForMaskedLM

Context length (tokens)

2,048

Layers

80

Hidden size

2,560

Feed-forward size

6,912

Attention heads

40

Key/value heads

40

Head dimension

64

Vocabulary size

64

Model type

esmc

## Identity and Version

Repository

biohub/ESMC-6B

Publisher

Biohub

Task

Fill mask

Modality

Text

Library

transformers

Parameters

6.4B parameters

Languages

en

Revision

af1602ba7406f521b11bf8f81d52af378cde09e4

First published

2026-05-19

Last updated

2026-09-16

## Files and Weights

15 files, 25.4 GB in total. The weights are 6 files totalling 25.4 GB in safetensors.

Weights6 files · 25.4 GB

Configuration4 files · 92.1 KB

Tokenizer2 files · 3.2 KB

Documentation1 file · 15.0 KB

Other1 file · 30.2 KB

Repository1 file · 1.6 KB

Every file

| File | Type | Size | SHA-256 |
| --- | --- | --- | --- |
| model-00001-of-00006.safetensors | Weights | 4.9 GB | 80cc4a51f218 |
| model-00002-of-00006.safetensors | Weights | 5.0 GB | 273740475dcd |
| model-00003-of-00006.safetensors | Weights | 5.0 GB | 00769f0e680a |
| model-00004-of-00006.safetensors | Weights | 4.9 GB | 1287dd34cb55 |
| model-00005-of-00006.safetensors | Weights | 5.0 GB | fef715f2b9f0 |
| model-00006-of-00006.safetensors | Weights | 582.8 MB | 7f88f2e9a884 |
| config.json | Configuration | 1.1 KB | — |
| model.safetensors.index.json | Configuration | 85.7 KB | — |
| modeling_esmc_remote.py | Configuration | 5.1 KB | — |
| special_tokens_map.json | Configuration | 171 B | — |
| README.md | Documentation | 15.0 KB | — |
| images/contact_pal.png | Other | 30.2 KB | — |
| .gitattributes | Repository | 1.6 KB | — |
| tokenizer.json | Tokenizer | 2.9 KB | — |
| tokenizer_config.json | Tokenizer | 327 B | — |

## License and Download

License

mit

Access

Open weights, no gate

Download size

25.4 GB

[Download from Biohub](https://huggingface.co/biohub/ESMC-6B)

Released by Biohub through its official repository on Hugging Face. [Read the license](https://opensource.org/license/mit).

## Memory Requirements

| Precision | Weights in memory |
| --- | --- |
| As published | 25.4 GB |
| 16-bit | 12.7 GB |
| 8-bit | 6.4 GB |
| 4-bit | 3.2 GB |

Weights only, from the published parameter count; the key-value cache and runtime add to this.

## Questions About ESMC-6B

### How much GPU memory does ESMC-6B need?

About 15.2 GB at 16-bit and 3.8 GB at 4-bit: the weights (6.4B parameters) plus a working margin. A long context needs more.

### What is the cheapest GPU to run ESMC-6B on?

At 16-bit, 1x MI300X from $1.85 an hour; at 4-bit, 1x MI300X from $1.85 an hour, at the lowest on-demand prices the SAVRN Index lists.

### Can I use ESMC-6B commercially?

Yes. ESMC-6B is released under MIT License. The MIT License is a short permissive license. It permits commercial use, modification and redistribution, provided the copyright notice and permission notice are included.

### What is ESMC-6B's context length?

2,048 tokens, from the maximum position embeddings in its published configuration.

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## Biohub

[All models and datasets](https://savrn.com/model-publishers/biohub)

## Versions

- [af1602ba7406](https://savrn.com/models/esmc-6b/versions/af1602ba7406) · current 2026-10-05

## Explore More

- [All fill mask models](https://savrn.com/models/tasks/fill-mask)
- [All models under mit](https://savrn.com/models/licenses/mit)
- [Model comparisons](https://savrn.com/models/comparisons)
- [The model directory](https://savrn.com/models)
- [Open model prices by host](https://savrn.com/ai-index/pricing/open-models)

## Source

- Repository metadata, read 2026-10-19.
- [Hugging Face record](https://huggingface.co/biohub/ESMC-6B)
- [How the hub is built](https://savrn.com/model-hub/methodology)
