Skip to content
MRI BrainKnee

fastMRI (knee and brain)

fastMRI: raw k-space and DICOM dataset of knee and brain MRI

Raw multi-coil k-space of 1,594 knee and 6,970 brain MRI scans from NYU Langone, plus about 10,000 clinical knee MRI exams as DICOM, released with Meta AI (FAIR) to benchmark machine-learning reconstruction of accelerated MRI.

Overview

fastMRI is a joint project of NYU Langone Health and Facebook AI Research (now Meta AI) that released one of the first large collections of raw MRI scanner data. It was built to train and compare machine-learning methods that reconstruct images from undersampled k-space, so that MRI exams can be made faster, and it powered the fastMRI reconstruction challenges.

Composition

The knee part holds fully sampled multi-coil k-space from 1,594 clinical knee scans, each a coronal proton-density volume with or without fat suppression, plus an emulated single-coil version. It is split into 973 training, 199 validation and 118 multi-coil test volumes, with further single-coil test and held-back challenge volumes; test and challenge volumes come undersampled and without ground truth. A separate DICOM collection adds 10,012 consecutive clinical knee exams from 9,290 patients with up to five standard sequences (coronal PD with and without fat suppression, sagittal PD, sagittal and axial fat-suppressed T2). The brain part holds raw k-space for 6,970 axial scans: T1-weighted with and without contrast agent, T2-weighted and FLAIR. Not every brain exam has every contrast. Prostate and breast sets released later are not covered here.

Acquisition

All raw data come from Siemens scanners at NYU: for the knee three 3 T systems (Skyra, Prisma, Biograph mMR) and a 1.5 T Aera with a 15-channel knee coil and a clinical 2D turbo spin echo protocol; for the brain 11 magnets at five locations, at 1.5 T (Avanto, Aera) and 3 T (Prisma, Skyra, Biograph, Tim Trio). Raw data were converted to the vendor-neutral ISMRMRD format and shipped as one HDF5 file per volume. The DICOM images come from a wider range of scanners and are mostly reconstructions of accelerated acquisitions.

Annotations

No clinical labels are included. The reconstruction targets are root-sum-of-squares images of the fully sampled data.

Known limitations

  • Brain k-space slices near and below the orbits were zeroed for de-identification, and only axial 2D brain data were released.
  • All raw data come from one vendor and one health system.
  • No age, sex or diagnosis information is published for the cohort.
  • Counts differ slightly between the paper and the website (for example 6,970 vs 7,002 brain scans).

Cohort

Aggregate numbers from the sources below. Bars are relative to the largest value.

Anatomy

subjects

  • Knee 9,290

License and access

Our reading of the license, not legal advice. Before you use the data, read the original license and confirm that your use is allowed. We take no responsibility for how you use a dataset. Full disclaimer

Access
Signed agreement

Sign a data use agreement, often reviewed by the provider

Access page

NYU Langone Health fastMRI Dataset Sharing Agreement

NYU grants a royalty-free license for internal research or education only, after an online application with an electronic signature. No selling, commercial exploitation or passing on of the data or of files derived from it, except to people under your direct supervision and in cited academic publications. Copies must be destroyed when the work is done.

The website says each sub-dataset has its own Data Sharing Agreement; the agreement text shown on the page is the one summarised here. The prostate and breast sub-datasets are not part of this entry.

Original license text Version read: Text on fastmri.med.nyu.edu as read on 2026-10-07 (undated; the page notes the agreement is subject to updates) Checked 2026-10-07

What you can do

  • No
  • Conditional
  • Yes
  • Conditional

What you can share

  • No
  • No
  • Not stated

What you must do

  • Yes
  • Share alike No
  • Yes
  • Conditional
  • Manuscript review No
  • Release code No
  • Return results No
  • Yes

Limits

  • Yes
  • Conditional

Citation

Knoll F, Zbontar J, Sriram A, et al. fastMRI: A Publicly Available Raw k-Space and DICOM Dataset of Knee Images for Accelerated MR Image Reconstruction Using Machine Learning. Radiol Artif Intell 2(1):e190007 (2020). doi:10.1148/ryai.2020190007; and Zbontar J, Knoll F, Sriram A, et al. fastMRI: An Open Dataset and Benchmarks for Accelerated MRI. arXiv:1811.08839.

All numbers

Every number on this page, as stored in stats.csv, with its source.

MeasureBreakdownValueSource
Scanstotal
raw volumes; the knee (1594) and brain (6970) sections add up to 8564
8,344zbontar2018
Section 1 (p. 2)
Scansanatomy=knee
fully sampled multi-coil raw knee scans (one volume each); DICOM exams are counted under studies
1,594zbontar2018
Section 4.2 (p. 7)
Scansanatomy=knee;contrast=PDw
coronal PD with fat suppression (798) and without (796)
1,594zbontar2018
Section 4.2 (p. 7)
Scansanatomy=knee;field_strength=1.5
raw knee scans on Siemens Aera 1.5T; the rest on 3T Skyra (663) Prisma (83) and Biograph mMR (153)
695zbontar2018
Table 2 (p. 8)
Scansanatomy=knee;split=train
raw knee volumes (multi-coil and single-coil)
973zbontar2018
Table 4 (p. 10)
Scansanatomy=knee;split=validation
raw knee volumes (multi-coil and single-coil)
199zbontar2018
Table 4 (p. 10)
Scansanatomy=knee;split=test
multi-coil test volumes; a further 108 single-coil test and 196 challenge volumes are held back
118zbontar2018
Table 4 (p. 10)
Scansanatomy=brain
fully sampled multi-coil raw brain scans; the website table now lists 7002
6,970zbontar2018
Section 4.3 (p. 7)
Scansanatomy=brain;field_strength=1.5 3,001zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;field_strength=3 3,969zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=T1w;field_strength=1.5
T1 without contrast
375zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=T1w;field_strength=3
T1 without contrast
407zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=T1w_ce;field_strength=1.5
T1 POST
849zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=T1w_ce;field_strength=3
T1 POST
641zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=T2w;field_strength=1.5 1,651zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=T2w;field_strength=3 2,515zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=FLAIR;field_strength=1.5 126zbontar2018
Table 3 (p. 8)
Scansanatomy=brain;contrast=FLAIR;field_strength=3 406zbontar2018
Table 3 (p. 8)
Studiesanatomy=knee
consecutive clinical knee DICOM image datasets (the website rounds to 10,000)
10,012knoll2020
Description of the Dataset, DICOM Dataset
Subjectsanatomy=knee
patients in the knee DICOM set only; patient counts for the raw data are not reported
9,290knoll2020
Description of the Dataset, DICOM Dataset

Sources

The keys used in the table above.