MS MARCO is a large scale information retrieval corpus that was created based on real user search queries using Bing search engine. The provided models can be used for semantic search, i.e., given keywords / a search phrase / a question, the model will find passages that are relevant for the search query.

The training data constist of over 500k examples, while the complete corpus consist of over 8.8 Million passages.

Version Histroy

As we work on the topic, we will publish updated (and improved) models.


Version 1 models were trained on the training set of MS Marco Passage retrieval task. The models were trained using in-batch negative sampling via the MultipleNegativesRankingLoss with a scaling factor of 20 and a batch size of 128.

They can be used like this:

from sentence_transformers import SentenceTransformer, util
model = SentenceTransformer('distilroberta-base-msmarco-v1')

query_embedding = model.encode('[QRY] ' + 'How big is London')
passage_embedding = model.encode('[DOC] ' + 'London has 9,787,426 inhabitants at the 2011 census')

print("Similarity:", util.pytorch_cos_sim(query_embedding, passage_embedding))


  • distilroberta-base-msmarco-v1 - Performance MSMARCO dev dataset ( MRR@10: 23.28