Company lists · Data refreshed September 2026

Top 25 Annotation services for machine learning based in the United States

RevenueBase identified 88 company matches for annotation services for machine learning associated with the United States as of September 2026 and tracks 7,863 professional contacts across them, including 908 with verified work emails. San Francisco is the largest hub.

This list covers company matches for annotation services for machine learning 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 September 27, 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 Sep 27, 2026 How this list was built
88Companies
7,863Contacts tracked
908Verified emails
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The 25 largest annotation services for machine learning based in the United States

Ranked by team size
Top 25 of 88 company matches for annotation services for machine learning based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 27, 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 matchScottsdale, AZ, United StatesHQ recorded Sep 27, 20261,001-5,0001,272 contacts →

Exact match

“Objectways is an AI data solutions company trusted by Fortune 500 enterprises and high-growth AI teams worldwide.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
2Exact matchNew York, NY, United StatesHQ recorded Sep 27, 20261,001-5,000977 contacts →

Exact match

“provides ML data operations support with Human-in-the-loop for LLMs and autonomous systems, focusing on AI/ML model training and annotation services.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
3Exact matchMiami, FL, United StatesHQ recorded Sep 27, 2026501-1,000899 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 · Sep 27, 2026 · View company records in RevenueBase
4Exact matchLos Angeles, CA, United StatesHQ recorded Sep 27, 2026201-500654 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 · Sep 27, 2026 · View company records in RevenueBase
5Exact matchStanford, CA, United StatesHQ recorded Sep 27, 202651-200526 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 · Sep 27, 2026 · View company records in RevenueBase
6Exact matchSan Francisco, CA, United StatesHQ recorded Sep 27, 202651-200356 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 · Sep 27, 2026 · View company records in RevenueBase
7Exact matchNew York, NY, United StatesHQ recorded Sep 27, 2026201-500328 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 · Sep 27, 2026 · View company records in RevenueBase
8Exact matchWilmington, DE, United StatesHQ recorded Sep 27, 2026201-500148 contacts →

Exact match

“Label Your Data is a data annotation & labeling company.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
9Exact matchNewark, DE, United StatesHQ recorded Sep 27, 2026201-500144 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
10Exact matchHampton, VA, United StatesHQ recorded Sep 27, 202651-200116 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 · Sep 27, 2026 · View company records in RevenueBase
11Exact matchRemote, United StatesHQ recorded Sep 27, 202651-200107 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
12Exact matchSeattle, WA, United StatesHQ recorded Sep 27, 2026n/a104 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 · Sep 27, 2026 · View company records in RevenueBase
13Exact matchWilmington, DE, United StatesHQ recorded Sep 27, 202611-5095 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 · Sep 27, 2026 · View company records in RevenueBase
14Exact matchSan Francisco, CA, United StatesHQ recorded Sep 27, 202651-20078 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
15Exact matchWilmington, DE, United StatesHQ recorded Sep 27, 20261,001-5,00076 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 · Sep 27, 2026 · View company records in RevenueBase
16Exact matchLevittown, NY, United StatesHQ recorded Sep 27, 20261,001-5,00074 contacts →

Exact match

“Anolytics is a leading provider of AI data solutions, with offices in India and the USA.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
17Exact matchBoston, MA, United StatesHQ recorded Sep 27, 202651-20059 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
18Exact matchNew York, NY, United StatesHQ recorded Sep 27, 2026501-1,00054 contacts →

Exact match

“At Keymakr, we provide exceptional image and video data annotation, data creation, data collection, and data validation services for AI/ML computer vision projects of all sizes.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
19Exact matchHouston, TX, United StatesHQ recorded Sep 27, 202611-5054 contacts →

Exact match

“Our mission is to help AI solutions save costs and increase performance.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
20Exact matchAustin, TX, United StatesHQ recorded Sep 27, 202651-20048 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
21Exact matchBellevue, WA, United StatesHQ recorded Sep 27, 202651-20045 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 · Sep 27, 2026 · View company records in RevenueBase
22Exact matchCherry Hill, NJ, United StatesHQ recorded Sep 27, 202611-5039 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 · Sep 27, 2026 · View company records in RevenueBase
23Exact matchUnion City, CA, United StatesHQ recorded Sep 27, 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 · Sep 27, 2026 · View company records in RevenueBase
24Exact matchBoston, MA, United StatesHQ recorded Sep 27, 202651-20030 contacts →

Exact match

“Every vision model starts with labeled data.”

Recorded in the RevenueBase company graph · Sep 27, 2026 · View company records in RevenueBase
25Exact matchPeachtree Corners, GA, United StatesHQ recorded Sep 27, 2026501-1,00026 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 · Sep 27, 2026 · View company records in RevenueBase

Showing 25 of 88 annotation services for machine learning based in the United States

See the full list, filter by size, metro and specialty, and access 908 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Annotation services for machine learning based in the United States at a glance

As of Sep 27, 2026
11.5%Verified-email coverage
89.4Average contacts per company
51-200Median size (employees)
13.6%Largest-city concentration · San Francisco
Sep 27, 2026Page data refreshed

Companies by employee count

1-10
23
11-50
19
51-200
26
201-500
11
501-1,000
4
1,001-5,000
4
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 88 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 “annotation services for machine learning” 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 908 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 September 27, 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 “annotation services for machine learning”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many annotation services for machine learning are there based in the United States?

RevenueBase identified 88 company matches for annotation services for machine learning associated with the United States as of September 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?

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

Which city has the most annotation services for machine learning?

San Francisco leads with 12 company records, followed by New York (9) and Los Angeles (5).

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 908 professional contacts with verified work emails tracked across these 88 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 September 27, 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.