Expert contributors for every AI training need.

We source, vet, and deploy domain experts into your annotation platforms and training pipelines — delivering the data points your models need, faster than anyone.

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rlhf_comparison_batch_41.json
Pair 7 of 30
Which response is more helpful, harmless, and honest?
Prompt: "Explain the difference between supervised fine-tuning and RLHF in language model training."
Response A

SFT trains on labeled examples with correct answers. RLHF uses human preferences to train a reward model, then optimizes the language model using reinforcement learning (PPO). RLHF better captures nuanced quality...

Response B
PREFERRED

SFT teaches the model to imitate — it learns from example outputs. RLHF teaches the model to improve — it learns from human judgments about what's better. Think of SFT as "learn to write like this" and RLHF as "learn what good writing is."

Helpfulness4/5
Accuracy5/5
Harmlessness5/5
Conciseness4/5
IAA Score:0.91|Annotator:Expert #1203
✓ QA Passed

Powering contributor pipelines for leading AI companies

Toloka
Datamundi
Mindrift
Scale
Snorkel
iMerit
Mistral
Toloka
Datamundi
Mindrift
Scale
Snorkel
iMerit
Mistral

What makes Braintrust unique in human data

Most providers rely on fragmented, multi-step screening — separate skills tests, identity checks, and days of back-and-forth. AIR's unified assessment covers skills, reasoning, language, and identity in a single session, qualifying contributors in under 30 minutes at dramatically higher conversion rates.

Our edge:
2M+ Talent Network
×
AIR Unified Assessment
Better talent quality
More engaged contributors
Faster deployment
Higher completion rates
Hit data timelines
AIR Assessment Scorecard
AIR Unified Assessment
< 30 min
to fully qualify a contributor
Skills & reasoning evaluated
Identity verified (IDV)
Language proficiency assessed
All in one unified session
1
Consultative Alignment

Project Requirements

We start by deeply aligning with you on the exact project requirements before a single expert is sourced. Every detail is locked in upfront.

Data type & format needed
Definition of success
Timeline & milestones
# of data points required
Systems & tools in use
QA process & quality bar
Expert domain requirements
NDA & security requirements
Project Alignment
2
Talent Network
Global Sourcing

The Talent Network

Once requirements are locked, we tap into our proprietary 2M+ Talent Marketplace. We instantly match your requirements against millions of professionals globally.

3
AI-Powered Screening

AIR Assessment & Security

< 30 minfull assessment
Unifiedskills + IDV in one session
Higher conversionvs. fragmented tools

Unlike tools that run skills tests, IDV, and background checks as separate steps, AIR conducts a unified assessment — evaluating skills, reasoning, language, and verifying identity all in a single conversational session. The result: qualified contributors in under 30 minutes, with higher completion rates and less drop-off.

AIR systematically assesses:

  • Behavioral fit
  • Technical skills
  • Reasoning ability
  • Language proficiency
  • Soft skills
  • Intent & motivation
AIR Assessment Scorecard
The Result

Faster deployment. Higher conversion. Less drop-off.

Because skills, reasoning, and identity are verified in one unified session, qualified contributors enter your pipeline in hours — not days. Higher-quality vetting upfront means less churn and stronger output quality throughout the project.

< 30 min
to qualify
Higher
conversion rate
Same day
deploy ready
4
Project Management
Guaranteed Execution

End-to-End Project Management

We don't just hand you a list of names. We manage the full output of the experts, ensuring they complete the work and create high-quality datasets on time.

The Braintrust Advantage: Most others rely on manual screening and messy spreadsheets, leading to huge drop-off rates and missed deadlines. Our automated, managed process prevents churn and guarantees delivery.

Need high-quality AI training data at scale?

Our managed team of domain experts delivers RLHF, annotation, and evaluation at enterprise speed.

Book a Demo →

Real experts across
every discipline.

Our contributors aren't generic crowd workers — they're credentialed professionals performing specialized work across every domain your AI training pipeline demands.

Expert contributor working on AI data annotation
50+ Languages100+ Countries50+ Disciplines

The people behind
the data.

Doctors reviewing medical AI output. Engineers validating code generation. Linguists annotating in their native language. Every contributor is matched by proven expertise — not just availability.

Join 2M+ verified experts

Data & AI Annotation

AI Annotation SpecialistData AnnotatorHuman-in-the-loop QAAI TrainerPrompt EngineerAI Conversational DesignerGPT SpecialistLinguistic AnnotatorAudio TranscriberTranscription QALabeling QA SpecialistImage / Video TaggerTaxonomy DesignerContent Rater

Software Engineering

Backend & API DevelopmentFrontend & UI EngineeringFull Stack EngineeringDevOps & AutomationData EngineeringCloud Architecture & InfraSecurity & Access ControlQA & Test EngineeringMobile DevelopmentPlatform Engineering

Regulated Domains

Health & Life SciencesLaw & PolicyFinance & AccountingConsulting & StrategyCompliance & RiskPrivacy & EthicsInsurance & BenefitsGovernance & Standards

Creative & Content

Content & CopywritingMarketing & Brand StrategyDesign & Visual CommunicationSocial & CommunityAdvertising & CampaignsUX Writing & ResearchCreative DirectionMultimedia & Production

Product

Product ManagementTechnical PMGrowth & Ops StrategyBusiness AnalysisProduct OwnershipPlatform & Tooling StrategyUser ResearchWorkflow Optimization

STEM & Technical Domains

PhysicsChemistryBiology / Life SciencesEnvironmental ScienceElectrical / Mechanical EngMathematics / StatisticsQuantitative AnalysisData Science / AI ResearchMachine Learning Engineering

Multi-language capabilities across all categories — find Python developers who speak Swedish, or medical annotators fluent in Mandarin.

2M+
Vetted Experts
Credentialed professionals across every major domain, ready to deploy
100+
Countries
Global sourcing for culturally-aware, multilingual data operations
50+
Languages
Native-level contributors for multilingual annotation and evaluation
Days
Ramp Time
From kickoff to production — we move fast without sacrificing quality

Trusted by frontier AI labs worldwide.

Join the companies building the next generation of AI with Braintrust human data infrastructure.

Book a Demo →

Why teams trust Braintrust

We combine the scale of a platform with the rigor of managed services.

Your systems, our people

Our contributors work directly inside your environment — your annotation platform, your internal tools, your workflows. Your data stays secure, and we manage the people delivering the outcomes.

Speed that compounds

Ramp thousands of contributors in days, not weeks. Our pre-vetted network means we skip the months-long recruiting cycle that slows down competitors.

Quality through vetting

AIR's unified assessment layer — covering skills, reasoning, language, and identity in one session — converts better because it's faster for contributors and more rigorous for clients. Quality is built into the entry point, not bolted on as post-hoc dashboards.

True global coverage

100+ countries, 50+ languages, every time zone. Find niche experts others can't — Emirati Arabic linguists, Brazilian Portuguese coders, Japanese medical reviewers.

End-to-end managed services

We handle the full lifecycle — from sourcing to delivery — so your team can focus on building models, not managing people.

Expert contributors collaborating on AI training data
2M+

Vetted experts,
deployed in days.

Every contributor is sourced from our 2M+ network, assessed through AIR, identity-verified, and calibrated before they touch your data.

Global Expert Sourcing

Source from 2M+ vetted experts across 100+ countries. Find niche domain specialists in days.

2M+ experts

AI-Powered Vetting

AIR conducts voice interviews, skills evaluations, and customizable scoring frameworks.

AI-assessed

IDV & Background Checks

Identity verification, NDA enforcement, and screening for enterprise compliance.

SOC 2 compliant

Funnel & Deployment

Full funnel management — sourcing, calibration, onboarding, and seamless deployment.

Full lifecycle

Quality Assurance

Multi-layer QA — gold standard checks, feedback loops, and reporting.

Multi-layer QA

Dedicated PMs

Dedicated PM per engagement — timelines, SLAs, standups, and delivery metrics.

Always-on

Let’s scope your AI data project.

Our team will help you define the right data pipeline for your model’s needs.

Book a Demo →

Expert contributors for every AI data type

Whatever your training pipeline needs — RLHF, annotation, evals, red teaming — we supply the people to get it done.

Most Requested

RLHF Contributors

Domain experts who rate, rank, and compare model outputs — providing the human preference signals your post-training pipeline needs.

Enterprise scale →

Data Annotators & Labelers

Structured annotation across text, image, video, and audio. Multi-language, multi-domain capability.

Multi-modal →

Model Evaluators

Trained evaluators assessing AI outputs for accuracy, safety, and domain correctness.

Custom rubrics

Red Team Experts

Adversarial specialists probing your models for vulnerabilities and harmful outputs.

Pre-launch safety

Prompt Engineers

Specialists testing and optimizing prompt designs across input patterns and edge cases.

Input optimization

Domain Expert Reviewers

Credentialed specialists — doctors, lawyers, engineers, scientists — who validate AI output accuracy and provide authoritative corrections.

Verified Results
Across Human Data
Workflows

Proven performance backed by real client deployments — not hypothetical benchmarks.

Deployed across Fortune 500 AI teams

+25,000

contributors
in the past 18 months

For a leading data labeling vendor, we placed over 25,000 contributors in the past 18 months, scaling to thousands/month to support high-volume multilingual and compliance-heavy pipelines.

Unlike closed platforms with hidden metrics, Braintrust gives you full visibility into who you're hiring — and how they perform.

10,000+

candidate assessments
per month

For a leading AI Training Data vendor, AIR powered 10,000+ candidate assessments/month, enabling them to onboard over 4,000+ fully vetted contributors/month into live client projects.

Most vetting tools stop at a score. We give you explainability — every score is backed by a transcript and audit trail.

< 3 days

to launch
full-service projects

For a leading data labeling vendor, we helped them launch full-service projects in <3 days while simultaneously running AIR-based assessments around the clock to screen thousands of internal contributors.

Most platforms lock you into their contributors or tools. Braintrust gives you both flexibility and speed — at scale.

AI Training Data FAQ

Common questions about expert sourcing, contributor management, and working with Braintrust.

Get expert contributors deployed — fast

Tell us what your AI pipeline needs. We'll source, vet, and deploy the right people — into your systems, on your timeline.

Contact Sales