Model reference · open weights
JaColBERTv2.5 is an open-weight embedding model from answerdotai. JaColBERTv2.5 (FP32) weighs 223 MB; the smallest configuration that runs it is RTX 3060 12 GB.
JaColBERTv2.5 is a sentence-similarity model developed by answerdotai for Japanese language tasks. It contains 111M parameters and supports a context length of 512 tokens. The model is released under the MIT license.
Summary of the answerdotai/JaColBERTv2.5 model card, 2026-10-01
What it is
| Released by | answerdotai |
|---|---|
| Type | Embedding models |
| Task | Embeddings |
| Parameters (lead) | 111M |
| Context | 512 tokens |
| Runs with | RAGatouille |
| Based on | cl-tohoku/bert-base-japanese-v3, bclavie/JaColBERT |
| Released | 2024-07-25 |
| Popularity | 2k downloads / month |
| Weights | 223 MB (JaColBERTv2.5 (FP32), file size) |
| Licence | Open weights |
What it runs on
Weights 223 MB (file size) · overhead about 1.1 GB.
| Card | Runs | Counted memory |
|---|---|---|
| RTX 3060 12 GB | fits | 11.6 GB |
| RTX 4060 Ti 16 GB | fits | 15.4 GB |
| RTX 3090 24 GB | fits | 23.4 GB |
| RTX 4090 24 GB | fits | 23.4 GB |
| RTX 5090 32 GB | fits | 31.0 GB |
| L40S 48 GB | fits | 44.0 GB |
| A100 80 GB | fits | 78.2 GB |
| H100 80 GB | fits | 78.1 GB |
| RTX PRO 6000 Blackwell 96 GB | fits | 93.8 GB |
| DGX Spark (GB10) 128 GB unified | fits | 107 GB |
| H200 141 GB | fits | 138 GB |
| B200 180 GB | fits | 176 GB |
Estimates, not measurements: the weights are the build's file size. No cache grows with use; a batch of inputs needs working memory of its own. Counted memory is 92 % of what CUDA reports for the card.
From the model card
Model weights for the final JaColBERTv2.5 checkpoint, using an entirely overhauled training recipe and trained on just 40% of the data of JaColBERTv2.
This model largely outperforms all previous approaches, including JaColBERTV2 multilingual models such as BGE-M3, on all datasets.
This page will be updated with the full details and the model report in the next few days.
@misc{clavié2024jacolbertv25optimisingmultivectorretrievers,
title={JaColBERTv2.5: Optimising Multi-Vector Retrievers to Create State-of-the-Art Japanese Retrievers with Constrained Resources},
author={Benjamin Clavié},
year={2024},
eprint={2407.20750},
archivePrefix={arXiv},
primaryClass={cs.IR},
url={https://arxiv.org/abs/2407.20750},
}
Quoted from the model card on Hugging Face — the full card is behind the Hugging Face link above.