The independent guide to human data companies

RLHF, expert data, evaluations, red teaming, and RL environments. Find vendors that match your workload, security needs, and buying model, with every fact linked to its source.

Explore the landscape Read the buyer’s guide

18vendors profiled: Managed services, expert networks, platforms, and dataset sellers.
44primary sources: Vendor sites, trust portals, and company releases. No listicles.
0paid placements: Nobody pays to appear or to change their position.

Who covers what

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Published workload coverage for 18 human data vendors. Click a column to see those vendors.

Which workloads each vendor publicly describes
Vendor	RLHF & preference	Expert demos	Evals & red teaming	RL environments	Speech & multilingual	Vision & physical AI	Self-serve	Off-the-shelf data
Appen	Yes	No	Yes	Yes	Yes	Yes	No	No
Centific	Yes	No	Yes	Yes	Yes	No	No	Yes
Defined.ai	No	No	Yes	No	Yes	No	No	Yes
Handshake AI	Yes	Yes	No	No	No	No	No	No
iMerit	Yes	Yes	Yes	Yes	No	Yes	No	No
Innodata	Yes	No	Yes	No	No	No	No	Yes
Invisible Technologies	Yes	Yes	Yes	No	No	No	No	No
Labelbox	Yes	Yes	Yes	Yes	No	No	No	No
Mercor	No	Yes	Yes	No	No	No	No	Yes
micro1	No	Yes	Yes	Yes	No	Yes	No	Yes
Prolific	Yes	Yes	Yes	No	No	No	Yes	No
Sama	Yes	No	Yes	No	No	Yes	No	No
Scale AI	Yes	No	Yes	No	No	Yes	No	No
Snorkel AI	No	Yes	Yes	No	No	No	No	No
Surge AI	Yes	Yes	Yes	Yes	No	No	No	Yes
TELUS Digital	Yes	No	Yes	No	No	Yes	No	Yes
Toloka	Yes	No	Yes	Yes	No	Yes	Yes	Yes
Turing	No	Yes	No	Yes	No	No	No	Yes
Vendors	13	10	16	8	3	7	2	9

Based on each vendor’s published categories and capabilities. A filled dot means the vendor describes this workload publicly; it is not a quality judgment.

Vendor landscape

18 vendors, checked November 8, 2026. Use filters for category, buying model, published certifications, and public pricing. Select up to four to compare side by side.

Human data vendors in alphabetical order with buying model, ownership, published certifications, and pricing
Vendor	Buying model	Ownership	SOC 2	ISO 27001	ISO 42001	HIPAA	Pricing
AppenManaged human data & RLHF	Managed service, Self-serve platform	Publicly listed	Published	Published	Not found	Not found	On request
CentificManaged post-training data	Managed service, Off-the-shelf datasets	Privately held	Not found	Not found	Not found	Not found	On request
Defined.aiData marketplace (off-the-shelf datasets)	Off-the-shelf datasets	Privately held	Not found	Published	Published	Published	Published
Handshake AIExpert network for AI training	Expert network	Subsidiary	Published	Not found	Not found	Not found	On request
iMeritManaged annotation & RLHF	Managed service, Self-serve platform	Subsidiary	Published	Published	Not found	Published	On request
InnodataManaged data annotation & RLHF	Managed service	Publicly listed	Not found	Not found	Not found	Not found	On request
Invisible TechnologiesManaged expert data & RLHF	Managed service, Expert network	Privately held	Published	Not found	Not found	Published	On request
LabelboxData platform	Expert network, Self-serve platform	Privately held	Published	Not found	Not found	Not found	On request
MercorExpert network for AI training & evals	Expert network, Off-the-shelf datasets	Privately held	Published	Not found	Not found	Not found	On request
micro1Expert human data	Expert network, Off-the-shelf datasets	Privately held	Not found	Published	Not found	Not found	On request
ProlificSelf-serve participant platform	Managed service, Self-serve platform	Privately held	Not found	Published	Not found	Not found	Published
SamaManaged annotation	Managed service	Privately held	Published	Published	Published	Not found	On request
Scale AIManaged human data & RLHF	Managed service	Privately held	Published	Published	Not found	Not found	On request
Snorkel AIExpert data development	Expert network	Privately held	Published	Not found	Not found	Published	On request
Surge AIManaged expert human data & RLHF	Managed service, Expert network	Privately held	Not found	Not found	Not found	Not found	On request
TELUS DigitalManaged human data & annotation	Managed service, Off-the-shelf datasets	Subsidiary	Not found	Not found	Not found	Not found	On request
TolokaManaged post-training data	Managed service, Self-serve platform, Off-the-shelf datasets	Privately held	Published	Published	Not found	Not found	On request
TuringExpert human data (coding, STEM, knowledge work)	Expert network, Off-the-shelf datasets	Privately held	Published	Not found	Not found	Not found	On request

Alphabetical. A check means the vendor publishes it on its own site or trust portal; a dash means we found nothing public, so ask the vendor.

Research and comparisons

GuideNov 8, 2026 How to choose a human data vendor for AI training Seven decisions, in order: scope, buying model, expertise, QA, security evidence, commercials, and conflicts. ComparisonNov 8, 2026 Prolific vs Toloka ComparisonNov 8, 2026 Mercor vs micro1 ComparisonNov 8, 2026 Sama vs iMerit

Browse by workload

How this guide works

Every claim links to a public source, with the date we checked it.
No paid rankings. Vendors are listed alphabetically or by the filters you choose.
Pricing shown only where a vendor publishes it. Otherwise: contact vendor.

Read the methodology