Model reference · open weights

instructor

Embeddings hkunlp Embeddings 1 build Open weights 35k dl/mo

instructor is an open-weight embedding model from hkunlp. instructor-base (BF16) weighs 439 MB; the smallest configuration that runs it is RTX 3060 12 GB.

For self-hosting, compare this build's requirements below with the GPU you plan to rent.

  • Instructor is an instruction-finetuned text embedding model developed by hkunlp for the sentence-similarity task.
  • It generates task-specific embeddings for applications such as classification, retrieval, and clustering by using a provided instruction without requiring additional finetuning.
  • The model supports English, has a context length of 512 tokens, and is released under the apache-2.0 licence.

Summary of the hkunlp/instructor-base model card, 2026-10-01

What it is

Released byhkunlp
Released2022-12-20
VRAM439 MB for the weights

What it runs on

Memory and cards for instructor-base (BF16)

439 MBweights, file size
1.1 GBruntime overhead
CardRunsMemory
RTX 3060 12 GBfits11.6 GB
RTX 4060 Ti 16 GBfits15.4 GB
RTX 3090 24 GBfits23.4 GB
RTX 4090 24 GBfits23.4 GB
RTX 5090 32 GBfits31.0 GB
L40S 48 GBfits44.0 GB
A100 80 GBfits78.2 GB
H100 80 GBfits78.1 GB
RTX PRO 6000 Blackwell 96 GBfits93.8 GB
DGX Spark (GB10) 128 GB unifiedfits107 GB
H200 141 GBfits138 GB
B200 180 GBfits176 GB

From the model card

What hkunlp says about instructor

Read the model card

We introduce Instructor👨‍🏫, an instruction-finetuned text embedding model that can generate text embeddings tailored to any task (e.g., classification, retrieval, clustering, text evaluation, etc.) and domains (e.g., science, finance, etc.) by simply providing the task instruction, without any finetuning. Instructor👨‍ achieves sota on 70 diverse embedding tasks! The model is easy to use with our customized sentence-transformer library. For more details, check out our paper and project page!

**************************** Updates ****************************

Quick start

Installation

pip install InstructorEmbedding

Compute your customized embeddings

Then you can use the model like this to calculate domain-specific and task-aware embeddings:

from InstructorEmbedding import INSTRUCTOR
model = INSTRUCTOR('hkunlp/instructor-base')
sentence = "3D ActionSLAM: wearable person tracking in multi-floor environments"
instruction = "Represent the Science title:"
embeddings = model.encode([[instruction,sentence]])
print(embeddings)

Use cases

Calculate embeddings for your customized texts

If you want to calculate customized embeddings for specific sentences, you may follow the unified template to write instructions:

                          Represent the domain text_type for task_objective:

  • domain is optional, and it specifies the domain of the text, e.g., science, finance, medicine, etc.
  • text_type is required, and it specifies the encoding unit, e.g., sentence, document, paragraph, etc.
  • task_objective is optional, and it specifies the objective of embedding, e.g., retrieve a document, classify the sentence, etc.

Calculate Sentence similarities

You can further use the model to compute similarities between two groups of sentences, with customized embeddings.

from sklearn.metrics.pairwise import cosine_similarity
sentences_a = [['Represent the Science sentence: ','Parton energy loss in QCD matter'],
               ['Represent the Financial statement: ','The Federal Reserve on Wednesday raised its benchmark interest rate.']]
sentences_b = [['Represent the Science sentence: ','The Chiral Phase Transition in Dissipative Dynamics'],
               ['Represent the Financial statement: ','The funds rose less than 0.5 per cent on Friday']]
embeddings_a = model.encode(sentences_a)
embeddings_b = model.encode(sentences_b)
similarities = cosine_similarity(embeddings_a,embeddings_b)
print(similarities)

Information Retrieval

You can also use customized embeddings for information retrieval.

import numpy as np
from sklearn.metrics.pairwise import cosine_similarity
query  = [['Represent the Wikipedia question for retrieving supporting documents: ','where is the food stored in a yam plant']]
corpus = [['Represent the Wikipedia document for retrieval: ','Capitalism has been dominant in the Western world since the end of feudalism, but most feel[who?] that the term "mixed economies" more precisely describes most contemporary economies, due to their containing both private-owned and state-owned enterprises. In capitalism, prices determine the demand-supply scale. For example, higher demand for certain goods and services lead to higher prices and lower demand for certain goods lead to lower prices.'],
          ['Represent the Wikipedia document for retrieval: ',"The disparate impact theory is especially controversial under the Fair Housing Act because the Act regulates many activities relating to housing, insurance, and mortgage loans—and some scholars have argued that the theory's use under the Fair Housing Act, combined with extensions of the Community Reinvestment Act, contributed to rise of sub-prime lending and the crash of the U.S. housing market and ensuing global economic recession"],
          ['Represent the Wikipedia document for retrieval: ','Disparate impact in United States labor law refers to practices in employment, housing, and other areas that adversely affect one group of people of a protected characteristic more than another, even though rules applied by employers or landlords are formally neutral. Although the protected classes vary by statute, most federal civil rights laws protect based on race, color, religion, national origin, and sex as protected traits, and some laws include disability status and other traits as well.']]
query_embeddings = model.encode(query)
corpus_embeddings = model.encode(corpus)
similarities = cosine_similarity(query_embeddings,corpus_embeddings)
retrieved_doc_id = np.argmax(similarities)
print(retrieved_doc_id)

Clustering

Use customized embeddings for clustering texts in groups.

import sklearn.cluster
sentences = [['Represent the Medicine sentence for clustering: ','Dynamical Scalar Degree of Freedom in Horava-Lifshitz Gravity'],
             ['Represent the Medicine sentence for clustering: ','Comparison of Atmospheric Neutrino Flux Calculations at Low Energies'],
             ['Represent the Medicine sentence for clustering: ','Fermion Bags in the Massive Gross-Neveu Model'],
             ['Represent the Medicine sentence for clustering: ',"QCD corrections to Associated t-tbar-H production at the Tevatron"],
             ['Represent the Medicine sentence for clustering: ','A New Analysis of the R Measurements: Resonance 

Quoted from the model card on Hugging Face. The full card is behind the Hugging Face link above.

Benchmarks

Reported results

As published on the model card: the maker's own numbers, not measured by AxForge.

TaskDatasetMetricScore
ClassificationMTEB AmazonCounterfactualClassification (en)accuracy86.209
ClassificationMTEB AmazonCounterfactualClassification (en)ap55.763
ClassificationMTEB AmazonCounterfactualClassification (en)f181.261
ClassificationMTEB AmazonPolarityClassificationaccuracy88.360
ClassificationMTEB AmazonPolarityClassificationap84.188
ClassificationMTEB AmazonPolarityClassificationf188.318
ClassificationMTEB AmazonReviewsClassification (en)accuracy44.640
ClassificationMTEB AmazonReviewsClassification (en)f142.487
RetrievalMTEB ArguAnamap_at_127.383
RetrievalMTEB ArguAnamap_at_1043.024
RetrievalMTEB ArguAnamap_at_10044.023
RetrievalMTEB ArguAnamap_at_100044.026
RetrievalMTEB ArguAnamap_at_337.684
RetrievalMTEB ArguAnamap_at_540.884
RetrievalMTEB ArguAnamrr_at_128.094
RetrievalMTEB ArguAnamrr_at_1043.315
RetrievalMTEB ArguAnamrr_at_10044.313
RetrievalMTEB ArguAnamrr_at_100044.317
RetrievalMTEB ArguAnamrr_at_337.862
RetrievalMTEB ArguAnamrr_at_541.155
RetrievalMTEB ArguAnandcg_at_127.383
RetrievalMTEB ArguAnandcg_at_1052.032
RetrievalMTEB ArguAnandcg_at_10056.195
RetrievalMTEB ArguAnandcg_at_100056.272
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