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FiftyOne

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What FiftyOne is

FiftyOne Annotation for images helps AI and machine-learning teams find samples to label, automate annotation with AI, and connect labeling to model evaluation. It supports bounding boxes, polygons, segmentation masks, classifications, polylines, and SAM2 click-to-segment instance segmentation. A labeling agent can create pre-labels from natural-language prompts, which users can combine with human review.

Image projects can use multi-stage workflows with review stages, rejection loops, and quality gates. Listed annotation integrations include CVAT, Label Studio, V7, and Labelbox; vector search integrations include Qdrant, Redis, and Pinecone. Deployment options include cloud or multi-cloud, hybrid, on-premise, air-gapped, and managed services. FiftyOne says datasets stay in the customer's environment and are not stored or transmitted by the platform. It also supports anonymization of personally identifiable and protected health information.

FiftyOne is open source and listed for API, Linux, macOS, self-hosted, web, and Windows. Voxel51 describes it as a platform for AI builders and machine-learning teams working with multimodal data at scale. Team, Growth, and Custom plans are listed with contact-sales or custom-pricing billing; their seat, compute, and deployment allowances vary.

Who it suits

FiftyOne suits AI builders and machine-learning teams that need image annotation workflows connected to model evaluation. Teams can use its AI-assisted pre-labeling, human review stages, integrations, and deployment options for data that remains in their environment.

What it does well

  • Supports bounding boxes, polygons, masks, classifications, and polylines.
  • Natural-language prompts can generate pre-labels for human review.
  • Workflows can include review stages, rejection loops, and quality gates.
  • Datasets remain in the customer's environment, according to FiftyOne.
  • Supports anonymization of personally identifiable and protected health information.

What to know first

  • Team lists 8 user seats and 16 guest seats.
  • Team lists 2,800 hours per month of compute.
  • Team includes one production deployment and one dev/staging deployment.

Limits

The Team plan lists 8 user seats, 16 guest seats, 4 VPUs, 2,800 compute hours per month, one production deployment, and one dev/staging deployment. Growth lists 25 user seats, 100 guest seats, 20 VPUs, 14,000 compute hours per month, and three production and three dev/staging deployments.

Plans

PlanBilled and limitsPrice
TeamContact sales · 8 user seats · 16 guest seats · 4 VPUs · 2,800 hours/month compute · 1 production deployment · 1 dev/staging deployment · Unlimited data · Unlimited model inferenceOn request
GrowthContact sales · 25 user seats · 100 guest seats · 20 VPUs · 14,000 hours/month compute · 3 production deployments · 3 dev/staging deployments · On-premise or air-gapped deployments · Premium enterprise supportOn request
CustomGet custom pricing · Unlimited user seats · Unlimited guest seats · Unlimited VPUs · Unlimited production and dev/staging deployments · Dedicated customer success team · Professional servicesOn request

As voxel51.com lists them, read 5 Oct 2026. The maker's own page has the final word.

Getting started

  1. Visit https://voxel51.com/annotation/image.
  2. Choose a supported environment: API, Linux, macOS, self-hosted, web, or Windows.
  3. Select image samples for annotation.
  4. Use a natural-language prompt to generate pre-labels, then combine them with human review.
  5. Build a multi-stage workflow with review stages, rejection loops, or quality gates as needed.
  6. Choose a deployment option such as cloud, hybrid, on-premise, or air-gapped.

Verdict

Choose FiftyOne if your team needs flexible image annotation, AI-assisted pre-labeling, and connections to model evaluation. Teams comparing paid Team, Growth, or Custom plans should confirm the appropriate seat, compute, and deployment allowances with the provider.

Questions

Is FiftyOne open source?

Yes. FiftyOne is listed as open source.

What platforms does it support?

Its listed platforms are API, Linux, macOS, self-hosted, web, and Windows.

What image annotation types are supported?

Supported types include bounding boxes, polygons, segmentation masks, classifications, polylines, and SAM2 click-to-segment instance segmentation.

What integrations are listed?

Annotation integrations include CVAT, Label Studio, V7, and Labelbox. Vector search integrations include Qdrant, Redis, and Pinecone.

How are the Team, Growth, and Custom plans priced?

The Team and Growth plans are billed through contact sales. Custom pricing is available for the Custom plan.

Who makes FiftyOne?

Voxel51 makes FiftyOne. The company says it was founded in 2018 at the University of Michigan by Professor Jason Corso and PhD student Brian Moore.

Facts from FiftyOne's own pages

Agentic labeling
Users can prompt a labeling agent in natural language to generate pre-labels and combine them with human review. · voxel51.com, 5 Oct 2026
Annotation types
Image annotation supports bounding boxes, polygons, segmentation masks, classifications, polylines, and SAM2 click-to-segment instance segmentation. · voxel51.com, 5 Oct 2026
Company founding
Voxel51 says it was founded in 2018 at the University of Michigan by Professor Jason Corso and PhD student Brian Moore. · voxel51.com, 5 Oct 2026
Data handling
The security page states that FiftyOne does not store or transmit datasets and that data remains in the customer's environment. · voxel51.com, 5 Oct 2026
Deployment
FiftyOne deployment options include cloud or multi-cloud, hybrid, on-premise, air-gapped, and managed services. · voxel51.com, 5 Oct 2026
Founded
2018 · voxel51.com, 28 Sept 2026
Image workflows
The image annotation platform supports multi-stage workflows with review stages, rejection loops, and quality gates. · voxel51.com, 5 Oct 2026
Integrations
The official integrations documentation lists annotation integrations including CVAT, Label Studio, V7, and Labelbox, and vector search integrations including Qdrant, Redis, and Pinecone. · docs.voxel51.com, 5 Oct 2026
Intended users
Voxel51 describes FiftyOne as a platform for AI builders and machine-learning teams working with multimodal data at scale. · voxel51.com, 5 Oct 2026
Purpose
FiftyOne Annotation for images helps identify samples for labeling, automate annotation with AI, and connect labeling with model evaluation. · voxel51.com, 5 Oct 2026
Security
Voxel51 states that it maintains ISO 27001 certification and undergoes regular third-party penetration and vulnerability tests. · voxel51.com, 5 Oct 2026
Sensitive data
FiftyOne supports data anonymization to protect personally identifiable and protected health information. · voxel51.com, 5 Oct 2026
Support
The Team plan lists standard enterprise support, Growth lists premium enterprise support, and Custom lists a dedicated customer success team. · voxel51.com, 5 Oct 2026

Where FiftyOne stands on Freedom251

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