Company lists · Data refreshed November 2026

Top 25 Data labeling and annotation services based in the United States

RevenueBase identified 98 company matches for data labeling and annotation services associated with the United States as of November 2026 and tracks 6,278 professional contacts across them, including 861 with verified work emails. San Francisco is the largest hub.

This list covers company matches for data labeling and annotation services associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed November 6, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Nov 6, 2026 How this list was built
98Companies
6,278Contacts tracked
861Verified emails
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The 25 largest data labeling and annotation services based in the United States

Ranked by team size
Top 25 of 98 company matches for data labeling and annotation services based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 6, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchMiami, FL, United StatesHQ recorded Nov 6, 2026501-1,000954 contacts →

Exact match

“With 30+ years of experience in data annotation, we support AI innovators to build smarter AI.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
2Exact matchCambridge, MA, United StatesHQ recorded Nov 6, 2026501-1,000814 contacts →

Exact match

“CapeStart is a US-focused global technology and services company helping organizations turn AI, data, and software ideas into production-ready systems.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
3Exact matchLos Angeles, CA, United StatesHQ recorded Nov 6, 2026201-500660 contacts →

Exact match

“Productive Playhouse is the execution partner technical program managers trust when scale, compliance, and quality can’t slip.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
4Exact matchSan Francisco, CA, United StatesHQ recorded Nov 6, 202651-200366 contacts →

Exact match

“SuperAnnotate bridges the gap between cutting-edge AI innovation and the high-quality human data that powers it - helping advanced AI teams build more intelligent models.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5Exact matchNew York, NY, United StatesHQ recorded Nov 6, 2026201-500337 contacts →

Exact match

“Shaip, by Ubiquity, provides end-to-end AI data services-data collection, licensing, validation, transcription, and annotation-across text, audio, image, and video.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6Exact matchPalo Alto, United StatesHQ recorded Nov 6, 202651-200316 contacts →

Exact match

“Abaka AI delivers human intelligence data for frontier AI, helping power advanced systems through a trustworthy data platform.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
7Exact matchStanford, CA, United StatesHQ recorded Nov 6, 202651-200299 contacts →

Exact match

“Pareto.AI is a talent-first human data collection platform for AI research, empowering the top 0.01% of expert labelers to deliver the highest-quality training data.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
8Exact matchRemote, United StatesHQ recorded Nov 6, 202651-200144 contacts →

Exact match

“Roboflow creates software-as-a-service products to make building with computer vision easy.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
9Exact matchNewark, DE, United StatesHQ recorded Nov 6, 2026201-500142 contacts →

Exact match

“Wow AI | Powered by AIxBlock - is an.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10Exact matchSeattle, WA, United StatesHQ recorded Nov 6, 2026n/a120 contacts →

Exact match

“The AI Data Labeling Marketplace: Find, hire, and securely pay vetted AI Trainers/data labelers across 110+ countries & any domain expertise.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11Exact matchHampton, VA, United StatesHQ recorded Nov 6, 202651-200108 contacts →

Exact match

“Liberty Source PBC is a U.S-based provider of human-in-the-loop data services that help companies realize maximum value from their Artificial Intelligence, Machine Learning, and…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12Exact matchSan Francisco, CA, United StatesHQ recorded Nov 6, 202651-200106 contacts →

Exact match

“HumanSignal enables data science teams to build AI models with their company DNA.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13Exact matchWilmington, DE, United StatesHQ recorded Nov 6, 202611-50102 contacts →

Exact match

“CVAT (Computer Vision Annotation Tool) is a leading platform for building high-quality visual datasets for vision AI.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14Exact matchWilmington, DE, United StatesHQ recorded Nov 6, 20261,001-5,00083 contacts →

Exact match

“AI Workspace has bagged a unique position in deliberating Sourcing, Data Annotation, and Generative AI services thereby initializing supervised learning for Machine Learning…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15Exact matchBoston, MA, United StatesHQ recorded Nov 6, 202651-20062 contacts →

Exact match

“Centaur.ai data empowers you to build and deploy high-stakes AI.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
16Exact matchAustin, TX, United StatesHQ recorded Nov 6, 202651-20054 contacts →

Exact match

“Alegion has the most powerful and flexible annotation platform for training data in market.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
17Exact matchBellevue, WA, United StatesHQ recorded Nov 6, 202651-20044 contacts →

Exact match

“With a deep dedication to creating ground-breaking tools plus large-scale human insight, we address the pain points of curating data for machine learning and other artificial…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
18Exact matchCherry Hill, NJ, United StatesHQ recorded Nov 6, 202611-5040 contacts →

Exact match

“Data Labeler specializes in providing reliable and high-quality training data sets for Machine Learning/Artificial Intelligence initiatives.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
19Exact matchLos Angeles, CA, United StatesHQ recorded Nov 6, 202611-5039 contacts →

Exact match

“Worca provides human intelligence for AI.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
20Exact matchBoston, MA, United StatesHQ recorded Nov 6, 202651-20036 contacts →

Exact match

“Every vision model starts with labeled data.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
21Exact matchUnion City, CA, United StatesHQ recorded Nov 6, 2026201-50036 contacts →

Exact match

“AI Inspired by Data " maadaa.ai, founded in 2015, is a comprehensive AI data service company supplying the AI industry with professional data services in text, voice, image, and…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
22Exact matchBrooklyn, United StatesHQ recorded Nov 6, 2026n/a31 contacts →

Exact match

“Werkit is a talent-to-delivery studio: trained developers and data specialists do the building, and senior experts plan the work and check everything before it ships.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
23Exact matchPeachtree Corners, GA, United StatesHQ recorded Nov 6, 2026501-1,00029 contacts →

Exact match

“We are a data services company specializing in data collection and annotation for Large Language Models (LLM), generative AI, and computer vision.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
24Exact matchWilmington, DE, United StatesHQ recorded Nov 6, 202611-5026 contacts →

Exact match

“What does Oprimes do?”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
25Exact matchWilmington, DE, United StatesHQ recorded Nov 6, 202611-5021 contacts →

Exact match

“Labellerr is a cutting-edge SaaS platform that accelerates AI development for organizations by offering AI-powered data labeling and automation.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

Showing 25 of 98 data labeling and annotation services based in the United States

See the full list, filter by size, metro and specialty, and access 861 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Data labeling and annotation services based in the United States at a glance

As of Nov 6, 2026
13.7%Verified-email coverage
64.1Average contacts per company
11-50Median size (employees)
11.2%Largest-city concentration · San Francisco
Nov 6, 2026Page data refreshed

Companies by employee count

1-10
25
11-50
27
51-200
30
201-500
9
501-1,000
4
1,001-5,000
2
5,001-10,000
1

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 98 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies
Company records associated with the United States whose business descriptions match “data labeling and annotation services” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every displayed company carries at least one verified work email. RevenueBase tracks 861 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on November 6, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “data labeling and annotation services”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many data labeling and annotation services are there based in the United States?

RevenueBase identified 98 company matches for data labeling and annotation services associated with the United States as of November 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Sigma AI tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most data labeling and annotation services?

San Francisco leads with 11 company records, followed by New York (9) and Wilmington (7).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 861 professional contacts with verified work emails tracked across these 98 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on November 6, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.