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Frontier AI data lab building expert datasets, environments and evals

Snorkel AI is a frontier AI data lab that builds expert datasets, benchmarks, evaluations and environments for AI models and agents.

AI Panel Score

7.8/10

6 AI reviews

Reviewed

AI Editor Approved

What is Snorkel AI?

Snorkel AI is a frontier AI data lab that builds expert datasets, benchmarks, evaluations and runnable environments for frontier model and agent development, delivered as a service rather than a labeling app your team runs. Teams buy off-the-shelf Snorkel Data Series datasets with rubrics, difficulty tiers and eval slices, commission custom data development such as bespoke datasets, RL environments and benchmark expansions, or have Snorkel build specialized agents for high-consequence enterprise workflows. Quality comes from calibrated expert review, rubrics, programmatic checks and provenance tracking, under SOC 2 Type 2 compliance. Pricing is quote-based after a scoped discovery call, with sample data available before purchase; no self-serve plan exists. TopReviewed's six-seat AI review panel scored it 7.8/10, praising a customer base that includes Experian, Wayfair, Rox and the Defense Innovation Unit alongside a $350 million Series E at a $3.5 billion valuation, while noting that no price is published and every deal is quoted. It fits AI teams that need expert training and evaluation data at scale.

About Snorkel AI

Snorkel AI is a frontier AI data lab that builds the data and environments behind advanced AI models and agents. Instead of selling labeling software, it delivers expert data development as a service: datasets, benchmarks, evaluations and environments built with its own credentialed domain experts.

It sells three ways. The Snorkel Data Series offers off-the-shelf, curriculum-structured datasets and agentic environments with rubrics, reviewer guidance, difficulty tiers and eval slices built in, refreshed quarterly. Custom data development covers task specification and rubric design, bespoke datasets, RL environments and benchmark expansions. Specialized agents are custom-built for high-consequence enterprise workflows such as credit decisioning, insurance underwriting and clinical diagnostics.

Quality rests on calibrated expert review, rubrics and programmatic checks, adjudication and provenance tracking. Snorkel works across text, code, image, audio and video, and its environments support SFT trajectory generation, RL with verifiable rewards, and evaluation from a single asset. It maintains SOC 2 Type 2 compliance and works on proprietary, sensitive and regulated data.

The company was founded out of the Stanford AI Lab in 2019 on research into data programming and weak supervision, and originally sold Snorkel Flow, a programmatic-labeling platform. It now works with leading frontier AI labs and enterprises, and in September 2026 raised a $350M Series E at a $3.5B valuation.

Features

AI

  • Agents' Last Exam

    Evaluates agents on long-horizon, economically valuable professional workflows with verifiable outcomes.

  • CUA-Bench, BigLaw Bench, and Terminal-Bench Science

    Collaborative domain-specific benchmarks evaluating agents on professional software, legal research, and scientific workflows.

  • Continual Learning Bench

    Measures whether AI agents improve performance across sequential, stateful tasks.

  • OSWorld 2.0

    Evaluates computer-use agents on long-horizon workflows spanning web and desktop environments.

  • Senior SWE-Bench

    A benchmark and live leaderboard that evaluates coding agents on realistic senior-level software engineering tasks.

  • SlopCode Bench

    Measures how code quality changes as coding agents repeatedly modify and extend their own solutions.

  • Specialized Agents

    Builds custom agents grounded in enterprise-specific data, knowledge, workflows, and operating environments.

  • Terminal-Bench 3.0 / 2.1

    Evaluates AI agents on challenging, domain-diverse tasks within terminal environments.

Analytics

  • Benchmark Leaderboards

    Publishes model and agent performance results across Snorkel's portfolio of benchmarks.

Core

  • Data Development / Snorkel Data Series

    Provides custom datasets, benchmarks, evaluations, and environments built for frontier AI model and agent development.

  • Evaluate → Curate → Refine Workflow

    Snorkel's research-validated methodology and expert workflow loop for developing and improving training data.

  • Open Benchmarks Grants Program

    Supports open, community-driven benchmark creation and evaluation research for agentic AI.

  • Research Publications

    Publishes technical papers and articles on rubric design, RLVR, data mixing, spatial reasoning, and agent evaluation methods.

Support

  • Snorkel Reading Group

    A recurring forum examining emerging research in AI benchmarking, evaluation, data development, and agentic systems.

Preview

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Pricing Plans

Contact Sales

Contact sales

Snorkel AI sells expert data development as a service, not a self-serve labeling app: off-the-shelf Snorkel Data Series datasets and environments, custom data development (bespoke datasets, RL environments, benchmarks and evals), and custom agents for specialized enterprise workflows. No prices are published; pricing is by quote after a scoped discovery conversation. Off-the-shelf Data Series products carry the best pricing, sample data is available before purchase, and accelerated volume without advance notice can incur rush surcharges.

  • Snorkel Data Series off-the-shelf datasets and environments, refreshed quarterly
  • Custom data development: bespoke datasets, RL environments, benchmarks and evals
  • Custom agents for specialized enterprise workflows
  • Sample data available before purchase
  • Calibrated expert review with rubrics and programmatic checks
  • SOC 2 Type 2 compliance

AI Panel Reviews

The Decision Maker

The Decision Maker

Strategic bet, vendor viability, timing, adoption approval
8.2/10

Snorkel AI sells expert data development to enterprise buyers, but it is a quote-only commitment.

“A Stanford-born data lab that builds expert datasets, environments and evals as a service. The catch is opaque quote-only pricing.”

Experian, Wayfair, Rox, the Defense Innovation Unit. That customer list is the real signal here, because Snorkel AI sells to buyers who run their own vendor reviews and still picked it.

The vendor question is solid. Spun out of the Stanford AI Lab in 2019, Snorkel closed a $350M Series E in September 2026 at a $3.5B valuation. It builds expert datasets, RL environments and benchmarks as a service, and expert-in-the-loop review keeps a calibrated human check on quality. Scale AI is the obvious rival, but Snorkel sells itself as a research-driven data lab, not a volume shop.

The catch is the buy-in. There is no published price, and every engagement starts with a scoping call and a custom quote. This is an enterprise sale, not a swipe-the-card pilot. Run a scoped data project with one ML team for a quarter before committing a budget line.

Competitive Positioning8.0

A research-driven, expert-data alternative to Scale AI's outsourced-annotator model.

Reputation Risk8.5

Experian, Wayfair, Rox and the Defense Innovation Unit as customers make this an easy board defense.

Speed to Value7.5

Off-the-shelf Data Series datasets start fast, but custom data project scoping takes real ramp.

Strategic Fit8.0

Expert data development advances model output rather than just trimming annotation cost.

Vendor Viability8.5

A 2019 Stanford spinout with a $350M Series E at a $3.5B valuation in September 2026.

Pros

  • Strong customer base including Experian, Wayfair, Rox and the Defense Innovation Unit.
  • Well-funded after a $350M Series E at a $3.5B valuation in September 2026.
  • Off-the-shelf Snorkel Data Series datasets ship with rubrics, difficulty tiers and eval slices.
  • SOC 2 Type 2 compliance and support for sensitive, regulated data suit compliance-heavy buyers.

Cons

  • No published pricing; every engagement is scoped and quoted through sales.
  • Enterprise-only sales motion offers no self-serve way to evaluate the service.
  • Engagements still need your experts' time for rubric definition, data review and acceptance testing.

Right for

Enterprise AI teams who need expert-built training data and evals at scale.

Avoid if

Small teams who need cheap annotation without a custom-quoted contract.

The Domain Strategist

The Domain Strategist

Craft and strategy in the product's domain — adapts identity per category, same lens
8.2/10

Snorkel AI turns frontier data development into research-grade process, but the engagement model is consultative, not self-serve.

“Snorkel AI builds expert datasets, environments and rubric-guided pipelines for frontier model teams. For an ML platform owner picking a data substrate through 2029, the strategic call is process depth versus a custom-quote relationship.”

An ML platform owner buying Snorkel AI is choosing how training data gets manufactured for years, and the architecture is the right bet. Programmatic quality control runs alongside expert review at every stage, with deterministic graders and rubric-based verifiers, so quality lives in process rather than headcount you rehire. Rubric design pins down task specs and scoring before a single dataset is built — discipline that signals a team out of the Stanford AI Lab.

The process layer is where the craft sits. Expert-in-the-Loop Review pairs PhD reviewers with automated checks, and Failure and Disagreement Analysis closes coverage gaps the way Scale AI's pure-annotation model structurally can't. Founded in 2019 and backed by a $350M Series E at a $3.5B valuation, Snorkel is a durable bet.

But the catch is the engagement shape. There's no public pricing and no free tier — every contract is quoted after scoping and runs consultative, so this is a strategic partner, not a tool you spin up in a sprint.

Category Positioning8.2

Sits ahead of pure-annotation vendors by owning the data-centric process layer for frontier model teams.

Domain Fit8.3

Rubric Design and Failure and Disagreement Analysis match how senior ML teams actually close coverage gaps.

Integration Surface7.6

Model-agnostic delivery alongside major cloud and data platforms, plus on-prem deployment, fits enterprise ML stacks cleanly.

Long-term Implications8.0

A reusable library of datasets, environments and verifiers is a durable asset, though the consultative model deepens vendor reliance.

Strategic Depth8.5

Rubric-guided pipelines, meta-evaluation and difficulty calibration are genuine research craft, not a checklist.

Pros

  • Programmatic checks and rubric-based verifiers make data quality measurable and repeatable.
  • Rubric design fixes task specs and scoring before dataset construction begins.
  • Expert-in-the-Loop Review pairs PhD reviewers with automated verifiers for high precision.
  • On-prem and air-gapped deployment keeps sensitive data inside your environment.

Cons

  • No public pricing and no free tier; every engagement needs a sales conversation.
  • The full Snorkel data catalog is not public; seeing it takes a sales conversation.
  • Consultative model means slower onboarding than a self-serve labeling tool.

Right for

ML platform teams who manufacture large training datasets at frontier scale.

Avoid if

Small teams who need a self-serve labeling tool with transparent pricing.

The Finance Lead

The Finance Lead

Money, total cost of ownership, contracts, procurement math
7.6/10

Snorkel AI ships no commercial price and custom data development is the line finance underbudgets.

“Snorkel AI is quote-only, with no published contract figure to anchor a budget. Custom data development is scoped per engagement and rarely fits a fixed forecast.”

Snorkel AI publishes nothing commercial. Every engagement sells through sales. No list price or contract figure is public; the first number arrives in a scoped quote. Off-the-shelf Data Series products price best, and rushed volume risks surcharges.

TCO math. There is no software license to amortize; the data is the bill. Expert data development — credentialed domain experts building and reviewing the datasets you need — is quoted per scoped engagement, not per seat, so the dataset-development scope drives the real number. Sample data exists for evaluation, but there is no free tier to pilot on. Compare Scale AI, which also negotiates per project; Snorkel at least holds SOC 2 Type 2, which trims a compliance review.

Snorkel raised a $350M Series E in September 2026 at a $3.5B valuation, so vendor risk is low. However, every quote needs a sales call and a scoped data engagement, so model the full services spend before signing.

Billing & Procurement7.0

Federal buyers can use GSA MAS and other contract vehicles, but every quote still requires direct sales engagement.

Contract Flexibility7.3

Teams can start off-the-shelf, build custom, or mix both, but every deal is quoted and scoped through sales.

Pricing Transparency6.0

No commercial price is published; the first figure a buyer sees arrives in a scoped quote.

ROI Clarity8.2

Rubric-Guided Labeling Pipelines and Failure and Disagreement Analysis tie data spend to measurable model coverage gaps.

Total Cost of Ownership7.0

Custom data development is quoted per scoped engagement, making year-3 cost hard to forecast.

Pros

  • Off-the-shelf Data Series products carry the best pricing and fit a standing data budget.
  • SOC 2 Type 2 compliance and sensitive-data handling trim a real compliance cost.
  • Rubric Design and Programmatic Quality Control tie data spend to measurable model coverage.
  • A $350M Series E at a $3.5B valuation keeps vendor risk low.

Cons

  • No commercial price is published anywhere; every tier requires a sales call.
  • Custom data-development engagements are scoped one by one and hard to forecast at year 3.
  • No self-serve plan exists for small teams without an enterprise data budget.

Right for

Enterprise AI teams who need expert-built training data at scale.

Avoid if

Small teams who want a fixed, self-serve price.

The Domain Practitioner

The Domain Practitioner

Daily hands-on reality in the product's domain — adapts identity per category, same lens
7.8/10

Snorkel AI ships datasets with verifiers that drop into your pipeline, but there is no door in without a scoped contract.

“Snorkel AI delivers expert-built datasets with environments, verifiers and reward modules instead of a labeling tool your team runs. But there is no free tier, so a solo practitioner cannot test it.”

A data scientist's day-three test isn't the sample dataset — it's whether the delivered data still holds up as your pipeline drifts under it. Snorkel no longer sells Snorkel Flow, the labeling-function platform; it delivers expert-authored datasets with the environments, verifiers and reward modules to train and evaluate against them. Weak supervision, the research this 2019 Stanford AI Lab spinout was founded on, is no longer a tool you run yourself.

Workflow fit is genuine for teams with a training pipeline already running. Terminal-Bench+ stays compatible with the Harbor Terminal-Bench format, so it drops into existing pipelines, and one environment covers SFT trajectory generation, RL with verifiable rewards, and evaluation. Snorkel can ship the full verification layer or hand over tasks and reference solutions for a verifier your team owns. Scale AI leans on external human annotators; Snorkel leans on credentialed experts with provenance and audit trails.

The catch is the entry door. There's no free plan and no self-serve tier — every engagement opens with a scoping call and a custom quote. Engagements assume your team can define rubrics, review data and run acceptance tests, so a solo practitioner can't kick the tires.

Day-3 Reality8.0

Tasks are defined by requirements, not a prescribed solution path, so they don't lock you into one agent architecture.

Documentation Practitioner-Fit7.5

A versioned User Guide (v26.1) is public, but access to the work itself sits behind a scoped engagement.

Friction Surface7.0

No self-serve onboarding means every evaluation starts with a sales engagement, not a sandbox.

Power-User Depth8.3

Meta-evaluation, failure-and-disagreement analysis, and custom evaluators give advanced teams real depth.

Workflow Integration8.2

Harbor-compatible Terminal-Bench+ tasks and bring-your-own verifiers fit an existing training pipeline.

Pros

  • Datasets ship with reproducible execution harnesses, verifiers and reward modules, not just static files.
  • One environment asset supports SFT trajectories, RL with verifiable rewards, and evaluation.
  • Terminal-Bench+ stays compatible with the Harbor format, so it fits existing pipelines.
  • Custom benchmarks and rubric-based evals score the process as well as the final output.

Cons

  • No free plan or self-serve tier — every trial runs through sales.
  • Quote-only enterprise contracts price out small teams and individuals.
  • Engagements still need your team for rubrics, data review and acceptance testing.

Right for

ML teams who need benchmark-grade training and eval data without building it in-house.

Avoid if

Solo practitioners who want to test a tool before a sales call.

The Power User

The Power User

Daily human experience, onboarding, polish, learning curve, reliability
7.6/10

Snorkel AI replaces generic labeling with expert-built data, but the door is enterprise-only.

“Snorkel AI delivers expert-built datasets and environments instead of a labeling tool you run yourself. There is no free tier and no public price, which is the catch.”

The first thing you notice is the wall. No free plan, no trial number on the page, just a Request dataset samples button and a sales form. For a data lab spun out of the Stanford AI Lab in 2019, that is a confident bet that you already know you need it.

What earns its keep is the Snorkel Data Series, where curriculum-structured datasets arrive with rubrics, reviewer guidance, difficulty tiers and eval slices built in. Samples come first, so your team can inspect task design and formats before scoping a purchase. Scale AI sells you human annotators; Snorkel sells you credentialed experts steered by a published research method.

The catch is the entry point. Every contract is scoped and quoted through sales, so this is a procurement decision, not a Tuesday signup. Month three, with rubrics settled, a trained data team moves fast here. The first month is real homework.

Daily Polish7.5

The Data Series and rubric-guided pipelines are carefully built, though the public site leans more marketing than product detail.

Learning Curve7.4

Defining rubrics and reviewing samples is real upfront work, but a trained data team scales fast by month three.

Mobile Parity7.5

Mobile is not a use case for a data-development service, scored neutral.

Onboarding Experience6.8

No trial or self-serve path means the first ten minutes is a sales form, not the product.

Reliability Feel7.8

Provenance tracking, audit trails and SOC 2 Type 2 compliance signal a service built for serious workloads.

Pros

  • Programs scale into the tens of thousands of tasks, from golden eval sets to pre-training volume.
  • Strong Stanford research pedigree, with provenance tracking and audit trails built into quality control.
  • On-premise and air-gapped deployment keeps sensitive data fully in-house.
  • Expert-in-the-loop review pairs automation with calibrated human reviewers for quality control.

Cons

  • No free plan, no trial, and no public pricing means you cannot evaluate before a sales call.
  • Snorkel Data Series, custom data development and specialized agents are three offerings, not one product.
  • Defining rubrics and reviewing samples is real upfront work that first-month users will feel.

Right for

Enterprise AI teams who need expert training data at large scale.

Avoid if

Solo developers who want to try a tool before talking to sales.

The Skeptic

The Skeptic

Contrarian. Watch-outs, deal-breakers, broken promises, category patterns
7.6/10

Snorkel AI quietly became a data-services company, and a $3.5B valuation says the bet is real.

“Founded in 2019 out of the Stanford AI Lab, Snorkel AI raised a $350M Series E in 2026 at a $3.5B valuation. The catch is opacity: pricing is contact-only and no contract figure is published anywhere.”

Watch what a vendor sells, not what it pitched. Snorkel AI started as programmatic labeling software. The current homepage sells expert datasets and evaluation as a service. That pivot is the tell — and not a bad one. Open-source roots from 2019, a $350M Series E in 2026 at a $3.5B valuation, backed by Insight Partners, S32, Greylock and Lightspeed.

What I found holds up. Snorkel Flow no longer sells as a product, but the Snorkel Data Series ships curriculum-structured datasets with rubrics and difficulty tiers, and rubric-guided pipelines pair programmatic checks with calibrated human experts. Real capabilities, not roadmap slides. But the moat is the worry — Scale AI owns the frontier-lab data contracts, and Labelbox sells annotation cheaper.

The yellow flag is exit portability. Bespoke datasets and evaluation frameworks are built around your failure surface, so leaving means losing curation work, not just files. No public pricing; the first number arrives only in a scoped quote. Credible vendor. Just scope the engagement before you commit.

Competitive Differentiation7.4

Research-validated methodology plus expert-in-the-loop review is a real gap, but Scale AI and Labelbox crowd the data-services space.

Exit Portability6.9

Bespoke datasets and custom evaluation frameworks are built around your failure surface, so migration loses curation work.

Long-term Viability8.0

A $350M Series E at a $3.5B valuation with Insight Partners, S32, Greylock and Lightspeed backing signals a credible three-year bet.

Marketing Honesty7.5

Homepage leans on frontier-lab superlatives, but the named datasets and process steps are concretely described.

Track Record Match7.8

Founded 2019 from the Stanford AI Lab with a 2026 Series E — a pattern that matches surviving infrastructure vendors.

Pros

  • Strong funding signal: $350M Series E in 2026 at a $3.5B valuation with durable backers.
  • Off-the-shelf Snorkel Data Series datasets let teams start faster than a custom build.
  • Rubric-guided pipelines pair programmatic checks with calibrated human experts for quality control.
  • On-premise and air-gapped deployment options suit compliance-sensitive buyers.

Cons

  • No public pricing; every contract is scoped and quoted through sales.
  • Bespoke datasets and evaluation frameworks make exit portability weak.
  • Scale AI and Labelbox compete directly in the data-services market.

Right for

Enterprise ML teams who need bespoke training and evaluation datasets at scale.

Avoid if

Small teams who want a cheap self-serve annotation tool.

Buyer Questions

Common questions answered by our AI research team

Features

What kind of data does Snorkel AI actually produce?

Snorkel produces expert-built training data, including expert demonstrations and reasoning traces, preference labels and rankings, and rubrics with verifiable outcomes like unit tests and citation correctness. It also builds runnable environments such as repo/CLI tools and browser/GUI harnesses for frontier AI model development.

Features

Does Snorkel offer pre-built datasets or only custom work?

Snorkel offers both. Its Data Series provides curriculum-structured datasets with rubrics, reviewer guidance, difficulty tiers, and eval slices, while custom data development builds bespoke datasets, evals, and benchmark expansions when off-the-shelf coverage runs out.

Features

Can Snorkel build custom AI agents for enterprise use?

Yes. Snorkel builds specialized agents grounded in expert data, evaluated against task-specific rubrics and programmatic pass/fail criteria rather than generic benchmarks, applying the same rigor used for frontier model training to enterprise deployments.

Features

What benchmarks has Snorkel AI developed?

Snorkel has developed Terminal-Bench Science, Senior SWE-bench, Agents' Last Exam, OSWorld 2.0, Terminal-Bench 4.0, and contributed expert data to Harvey BigLaw Bench for legal AI research.

Features

How does Snorkel ensure labeling quality and reduce bias?

Snorkel's process relies on well-specified expert-level tasks, calibrated expert review, rubrics and programmatic checks, and adjudication with provenance tracking to reduce inconsistent labels and systematic reviewer bias.

Alternatives to Snorkel AI

Who Snorkel AI competes with, and how each one differs

Product Information

  • Company

    Snorkel AI
  • Founded

    2019
  • Pricing

    Contact for pricing
  • Free Trial

    Available

Platforms

web

About Snorkel AI

Snorkel AI is a Redwood City-based AI data development platform that uses programmatic labeling and expert feedback to build specialized datasets for LLMs and enterprise models.

Resources

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