SingularityCE vs Apptainer

SingularityCE8.6Visit Apptainer8.5Visit

Higher score SingularityCE #7 in Container Engines 8.6/10 Free plan Free plan✓ 2 of 4 features Visit SingularityCE

vs

Apptainer #8 in Container Engines 8.5/10 Free plan Free plan✓ 2 of 4 features Visit Apptainer

• SingularityCE fits best

  HPC, GPU, and secure Linux containers

• Apptainer fits best

  Rootless research and cross-platform container use

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Side by side

Feature	SingularityCE 8.6/10 Visit ↗	Apptainer 8.5/10 Visit ↗
At a glance
Editor score	8.6	8.5
Ranking	#7 in Container Engines	#8 in Container Engines
Best for	HPC, GPU, and secure Linux containers	Rootless research and cross-platform container use
Pricing model	Free	Free
Starting price	Free plan	Free plan
Free plan	✓	✓
Free trial	—	—
Deployment	Self-hosted	Self-hosted, Desktop
Platforms	Linux	Linux, Windows, macOS
Support	Email, Community, Docs	Docs
Integrations	4 integrations	8 integrations
Built for	Small business, Mid-market, Enterprise	Small business, Mid-market, Enterprise
Features SingularityCE 2/4 · Apptainer 2/4
Rootless mode	✓	✓
Image building	✓	✓
Kubernetes CRI	Not checked yet	Not checked yet
Windows containers	—	—
Specs
Image format	Both	Both
Runtime interface	Other	Other
Supported host OS	linux	Linux; Windows via WSL2; macOS via Linux VM
Our review
Pros	Supports GPU workloads and high-speed interconnects Builds, signs, verifies, and encrypts container images Runs native and OCI containers with unprivileged builds	Runs containers as unprivileged users with fakeroot support Builds read-only SIF images and writable sandbox containers Works with Docker, OCI registries, Podman, ORAS, IPFS, and Vault
Cons	Does not run natively on Windows or macOS Kubernetes CRI support is under development Primarily designed and verified for Linux environments	Windows use requires WSL2 and Linux virtualization macOS use requires a Linux virtual machine or Apple container approach Read-only SIF images may not suit workflows needing mutable images
Our verdict	SingularityCE is an open-source container platform for building and running portable, reproducible software environments on Linux. It is aimed at high-performance computing, shared systems, workstations, cloud systems, and HPC clusters.… Read the review →	Apptainer is an open-source container platform for creating, executing, encrypting, and sharing portable workloads. It is designed primarily for high-performance computing, enterprise performance computing, academia, and shared systems.… Read the review →

Strengths and trade-offs

• SingularityCE — where it wins

  • Supports GPU workloads and high-speed interconnects
  • Builds, signs, verifies, and encrypts container images
  • Runs native and OCI containers with unprivileged builds

  Where it doesn't

  • Does not run natively on Windows or macOS
  • Kubernetes CRI support is under development
  • Primarily designed and verified for Linux environments

• Apptainer — where it wins

  • Runs containers as unprivileged users with fakeroot support
  • Builds read-only SIF images and writable sandbox containers
  • Works with Docker, OCI registries, Podman, ORAS, IPFS, and Vault

  Where it doesn't

  • Windows use requires WSL2 and Linux virtualization
  • macOS use requires a Linux virtual machine or Apple container approach
  • Read-only SIF images may not suit workflows needing mutable images

• SingularityCE8.6/10 · Free plan

  A Linux-focused container engine for HPC, GPU workloads, and secure image execution.

  Visit SingularityCEFull verdict →
• Apptainer8.5/10 · Free plan

  A free, open-source container platform built for unprivileged, portable workloads.

  Visit ApptainerFull verdict →