OpenTrain AI records 1,469,348 monthly visits with +11.2% month-over-month growth and Contact for Pricing pricing. Polygres records 4,018 monthly visits with -52.3% growth and Freemium pricing.
Hire tested AI trainers and data labelers for RLHF, evaluation, and annotation
Graph, vector and text retrieval for AI agents on your Postgres
| Dimension / Metric | | |
|---|---|---|
| Official Domain | opentrain.ai | polygres.com |
| Pricing Model | Contact for Pricing | Freemium |
| Monthly Visits | 1.47M (1,469,348) | 4.02K (4,018) |
| MoM Traffic Delta | +147.68K (+11.2%) | -4.41K (-52.3%) |
| Primary Market & Share | 🇺🇸 United States (18.6%) | 🌐 Global (—) |
| Direct Visits / mo | 607.07K | 1.61K |
| User Rating | 4.2 | 4.1 |
| Supported Platforms | Website | Website |
Hire tested AI trainers and data labelers for RLHF, evaluation, and annotation
Post a project and receive a shortlist drawn from a network of more than 711,000 people across 240+ countries, available in 120+ languages.
Applicants pass automated interviews and domain skill assessments, and managed programs add live proctored testing, so candidates are matched on demonstrated ability rather than self-reported skills.
Hire managers can add experts straight into Label Studio, CVAT, Labelbox, Argilla, or another tool they already run, avoiding data migration.
Beyond standard labeling, the network covers RLHF preference ranking, DPO pair generation, reasoning verification, adversarial red teaming, and human benchmarking.
Graph, vector and text retrieval for AI agents on your Postgres
Query graph, vector, full-text and hybrid retrieval through one consistent interface instead of stitching multiple systems together.
The open-source pgGraph engine follows relationships across your records, enabling multi-hop and shortest-path retrieval without moving data.
Semantic search over embeddings combines with sparse and full-text matching so queries that mix meaning and exact terms still work.
A dashboard playground, CLI for imports and configuration, and a typed Python SDK make it straightforward to prototype and then ship.
AI-driven talent marketplace matching domain experts with AI labs, focusing more on long-term remote roles than short tasks.
AI-driven talent marketplace matching domain experts with AI labs, focusing more on long-term remote roles than short tasks.
Massive global pool of subject matter experts for RLHF and model training, but features less personalized curation.
Massive global pool of subject matter experts for RLHF and model training, but features less personalized curation.
SpecialistOffers crowdsourced data collection and annotation at scale, but lacks specialized frontier-model RLHF training workflows.
SpecialistOffers crowdsourced data collection and annotation at scale, but lacks specialized frontier-model RLHF training workflows.
Web search API and crawler built for AI agents
Search and inference APIs that give AI models real-time web data
SpecialistEnterprise-grade data labeling and annotation platform, but places more emphasis on tooling than direct expert recruitment.
SpecialistEnterprise-grade data labeling and annotation platform, but places more emphasis on tooling than direct expert recruitment.
AI search and retrieval platform for modern apps and commerce
SpecialistAdvanced multimodal data annotation platform with robust enterprise management tools, but relies more on software than managed talent.
SpecialistAdvanced multimodal data annotation platform with robust enterprise management tools, but relies more on software than managed talent.
The managed vector database and knowledge engine for production AI
Provides highly vetted human data and evaluation workforces for frontier labs, but caters primarily to enterprise clients.
Provides highly vetted human data and evaluation workforces for frontier labs, but caters primarily to enterprise clients.
Free / Open-sourceFree open course for prompt engineering and AI security
Free / Open-sourceFree open course for prompt engineering and AI security
Free / Open-sourceCommunity hub for data science, machine learning and AI practitioners
Free / Open-sourceCommunity hub for data science, machine learning and AI practitioners
