Papers › Exploring Simple Siamese Representation Learning

Exploring Simple Siamese Representation Learning

20 Nov 2020CVPR 2021 1arXiv:2011.10566archive 2025-07-28

Xinlei Chen, Kaiming He

Siamese networks have become a common structure in various recent models for unsupervised visual representation learning. These models maximize the similarity between two augmentations of one image, subject to certain conditions for avoiding collapsing solutions. In this paper, we report surprising empirical results that simple Siamese networks can learn meaningful representations even using none of the following: (i) negative sample pairs, (ii) large batches, (iii) momentum encoders. Our experiments show that collapsing solutions do exist for the loss and structure, but a stop-gradient operation plays an essential role in preventing collapsing. We provide a hypothesis on the implication of stop-gradient, and further show proof-of-concept experiments verifying it. Our "SimSiam" method achieves competitive results on ImageNet and downstream tasks. We hope this simple baseline will motivate people to rethink the roles of Siamese architectures for unsupervised representation learning. Code will be made available.

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Syntology Ran 34 of 39 code samples harvested from 11 repositories linked to this paper; 5 have no recorded run. Of those that ran: 7 ran · our draft was wrong; 2 ran · fixture could not drive it; 25 ran with no contract checked.

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26 repositories listed; official and paper-mentioned ones first.

facebookresearch/simsiam officialmentioned on GitHubpytorch report
FloCF/SSL_pytorch mentioned on GitHubpytorch report
IgorSusmelj/simsiam-cifar10 mentioned on GitHubpytorch report
PaperCodeReview/SimSiam-TF mentioned on GitHubtf report
PatrickHua/SimSiam mentioned on GitHubpytorch report
Reza-Safdari/SimSiam mentioned on GitHubpytorch report
SaeedShurrab/SimSiam-pytorch mentioned on GitHubpytorch report
Westlake-AI/openmixup mentioned on GitHubpytorch report
a07458666/simsiamfacenet mentioned on GitHubpytorch report
amro-kamal/SimSiam-Implementation mentioned on GitHubpytorch report
facebookresearch/clip-rocket mentioned on GitHubpytorch report
juneweng/byol-pytorch mentioned on GitHubpytorch report
krishnatarun/ssl_dgc mentioned on GitHubpytorch report
leaderj1001/SimSiam mentioned on GitHubpytorch report
lightly-ai/lightly mentioned on GitHubpytorch report
miszkur/SelfSupervisedLearning mentioned on GitHubtf report
nikheelpandey/SimSiam-PyTorch mentioned on GitHubpytorch report
open-mmlab/mmselfsup mentioned on GitHubpytorchApache-2.0 report
sayakpaul/SimSiam-TF mentioned on GitHubtf report
szq0214/S2-BNN mentioned on GitHubpytorch report
taoyang1122/pytorch-SimSiam mentioned on GitHubpytorch report
vturrisi/solo-learn mentioned on GitHubpytorch report
PaddlePaddle/PASSL paddleApache-2.0 report

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Code Syntology ran Syntology

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7ran · our draft was wrong
2ran · fixture could not drive it
25ran
5unverified

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SimSiam facebookresearch/simsiam/simsiam/builder.py official repository ran · metamorphic tier: deterministic licence not identified · pointer only · 492cc68fb1110aa3 · report
Bottleneck Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · metamorphic tier: invariant fingerprinted no licence file found · pointer only · 47df0764b5090ea2 · report
CL2L facebookresearch/clip-rocket/models.py community (archive-listed) ran · metamorphic tier: deterministic licence not identified · pointer only · bbe4c4713c60cb7b · report
CLIP facebookresearch/clip-rocket/models.py community (archive-listed) ran · metamorphic tier: deterministic licence not identified · pointer only · 4d45d7d0856d7377 · report
D PatrickHua/SimSiam/models/simsiam.py community (archive-listed) ran · fixture could not drive it MIT (permissive) · b2429807c9efa3f7 · report
D nikheelpandey/SimSiam-PyTorch/model.py community (archive-listed) ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · dc05a6f71458b31e · report
D leaderj1001/SimSiam/model.py community (archive-listed) ran fingerprinted MIT (permissive) · 38628e7af88c5ed9 · report
DropPath facebookresearch/clip-rocket/models.py community (archive-listed) ran · metamorphic tier: deterministic fingerprinted licence not identified · pointer only · 6bd663b5be82dccd · report
MLP FloCF/SSL_pytorch/torchselfsup/models/simsiam.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · bb30a29172efa151 · report
Model leaderj1001/SimSiam/model.py community (archive-listed) ran MIT (permissive) · 516cd76945c13b46 · report
PredictionMLP taoyang1122/pytorch-SimSiam/models/simsiam.py community (archive-listed) ran · metamorphic tier: deterministic Apache-2.0 (permissive) · 9d0e6a2eca652065 · report
ProjectionHead lightly-ai/lightly/lightly/models/simsiam.py community (archive-listed) ran fingerprinted MIT (permissive) · da76a8285671b345 · report
ResNet Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran no licence file found · pointer only · 0f2aaed67b1fc0a0 · report
ResNet101 Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · ed0e4015879df242 · report
ResNet152 Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · e6da00517c19b39c · report
ResNet18 Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · 4a6376067215c5f6 · report
ResNet34 Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · efbcdfcbc565884f · report
ResNet50 Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · 1ace917fd995e564 · report
ResidualAttentionBlock facebookresearch/clip-rocket/models.py community (archive-listed) ran · metamorphic tier: deterministic licence not identified · pointer only · 009322dbbfd98763 · report
SimSiam FloCF/SSL_pytorch/torchselfsup/models/simsiam.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · 815591f7486b47ff · report
SimSiam taoyang1122/pytorch-SimSiam/models/simsiam.py community (archive-listed) ran · metamorphic tier: deterministic fingerprinted Apache-2.0 (permissive) · d9b4a10391a8d49f · report
SimSiam a07458666/simsiamfacenet/src/models/simsiam.py community (archive-listed) ran · metamorphic tier: deterministic fingerprinted licence not identified · pointer only · 5ef921dde450036d · report
SimSiam lightly-ai/lightly/lightly/models/simsiam.py community (archive-listed) ran MIT (permissive) · fb0cb8a440e873f9 · report
SimSiam PatrickHua/SimSiam/models/simsiam.py community (archive-listed) ran MIT (permissive) · 32880b6d81ed25f9 · report
SimSiam nikheelpandey/SimSiam-PyTorch/model.py community (archive-listed) ran Apache-2.0 (permissive) · 752e4e769526a23c · report
SimSiamPredictionHead lightly-ai/lightly/lightly/models/simsiam.py community (archive-listed) ran MIT (permissive) · 7aa59b2768a14009 · report
SimSiamProjectionHead lightly-ai/lightly/lightly/models/simsiam.py community (archive-listed) ran MIT (permissive) · 4e65e79a1e2a3fcc · report
Transformer facebookresearch/clip-rocket/models.py community (archive-listed) ran · metamorphic tier: deterministic licence not identified · pointer only · 012204ec88654334 · report
get_backbone nikheelpandey/SimSiam-PyTorch/model.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · baecb6445a98aac2 · report
infer_batchnorm_class facebookresearch/clip-rocket/models.py community (archive-listed) ran · metamorphic tier: deterministic licence not identified · pointer only · d23738a6312f956e · report
prediction_MLP PatrickHua/SimSiam/models/simsiam.py community (archive-listed) ran MIT (permissive) · 18a041c1ad13c81f · report
prediction_MLP Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) ran · metamorphic tier: invariant no licence file found · pointer only · 4f89fc5dcdf63603 · report
projection_MLP PatrickHua/SimSiam/models/simsiam.py community (archive-listed) ran MIT (permissive) · 4eff742841c262a2 · report
SIAMLIP facebookresearch/clip-rocket/models.py community (archive-listed) unverified licence not identified · pointer only · bd3b410047cb6c47 · report
SimSiam ahmdtaha/simsiam/models/simsiam.py community (archive-listed) unverified no licence file found · pointer only · f2af91921deea94a · report
SimSiam Reza-Safdari/SimSiam/simsiam/model_factory.py community (archive-listed) unverified no licence file found · pointer only · c9eb23d22a1f6e19 · report
get_backbone ahmdtaha/simsiam/models/simsiam.py community (archive-listed) unverified no licence file found · pointer only · 1a35ab02b0214a3a · report
projection_MLP ahmdtaha/simsiam/models/simsiam.py community (archive-listed) unverified no licence file found · pointer only · cb99b702c75951a5 · report
drop_path identical code first harvested elsewhere ran · fixture could not drive it licence of this copy not recorded · 971ae8d2d8313e30 · report

Tasks

Representation LearningSelf-Supervised Image Classification

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Self-Supervised Image Classification ImageNet SimSiam (ResNet-50) Number of Params 24M #99 of 144 Archive leaderboard report
Self-Supervised Image Classification ImageNet SimSiam (ResNet-50) Top 1 Accuracy 71.3% #99 of 144 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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