Company lists · Data refreshed September 2026

Top 25 Prompt engineering platforms based in the United States

RevenueBase identified 95 prompt engineering platforms headquartered in the United States as of September 2026 and tracks 7,638 professional contacts across them, including 1,105 with verified work emails and 1,109 with mobile numbers. San Francisco is the largest hub.

This list covers prompt engineering platforms headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, how directly it supports the match, and when it was last checked. Data refreshed September 5, 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 HQ checked on every row Match evidence on every row Refreshed Sep 5, 2026 86% judged on-target in blind review
95Companies
7,638Contacts tracked
1,105Verified emails
1,109Mobile numbers
Explore all 95 companies → Free signup · no credit card · 500 free credits

The 25 largest prompt engineering platforms based in the United States

Ranked by team size
Top 25 of 95 prompt engineering platforms based in the United States, ranked by team size, largest first. Data refreshed Sep 5, 2026. Evidence rates how directly each company's own description names prompt engineering platforms: strong (names it), partial (names part of it), indirect (matched on its full profile rather than the summary shown). Click a count to unlock that company's people.
#CompanyHeadquartersEmployeesContacts
1Las Vegas, NV, United StatesHQ checked Sep 5, 202610001+4,886

“TELUS Digital AI & Data Solutions partners with a diverse and vibrant community to help our customers enhance their AI and machine learning models.”

Source: company website · checked Sep 5, 2026
2
Snorkel AIIndirect evidence
Redwood City, CA, United StatesHQ checked Sep 5, 2026201-500967

“Snorkel AI is the frontier AI data lab, helping teams build the data and environments behind high-performing frontier and agentic AI.”

Source: company website · checked Sep 5, 2026
3
Weights & BiasesPartial evidence
San Francisco, CA, United StatesHQ checked Sep 5, 2026201-500357

“Weights & Biases: the AI developer platform.”

Source: company website · checked Sep 5, 2026
4United StatesHQ checked Sep 5, 202651-200183

“The next-generation AI developer platform unifying the development and deployment of AI for the world.”

Source: company website · checked Sep 5, 2026
5Las Vegas, NV, United StatesHQ checked Sep 5, 202610001+173

“TELUS International AI Data Solutions partners with a diverse and vibrant community to help our customers enhance their AI and machine learning models.”

Source: company website · checked Sep 5, 2026
6
Fireworks AIIndirect evidence
San Mateo, CA, United StatesHQ checked Sep 5, 202651-200166

“Fireworks is the fastest way to build, tune, and scale AI on open models.”

Source: company website · checked Sep 5, 2026
7
Lightning AIPartial evidence
New York, NY, United StatesHQ checked Sep 5, 202651-200140

“The AI development platform - From idea to AI, Lightning fast.”

Source: company website · checked Sep 5, 2026
8
COMETIndirect evidence
New York, NY, United StatesHQ checked Sep 5, 202651-20085

“Comet has been building AI developer tools since 2017, first for teams training their own models, and later for those building LLM-powered agents.”

Source: company website · checked Sep 5, 2026
9
ZeromatterPartial evidence
Mountain View, United StatesHQ checked Sep 5, 202651-20066

“One platform to build, test, and train anything (still in ~stealth, more to come soon)”

Source: company website · checked Sep 5, 2026
10
StriveworksIndirect evidence
Austin, NC, United StatesHQ checked Sep 5, 202651-20057

“In 36 months, agentic AI systems will be an operating reality across major institutions.”

Source: company website · checked Sep 5, 2026
11
genai.worksIndirect evidence
San Francisco, CA, United StatesHQ checked Sep 5, 2026n/a40
Source: company website · checked Sep 5, 2026
12
Essential AIPartial evidence
San Francisco, United StatesHQ checked Sep 5, 202611-5029

“Essential AI is on a mission to make frontier AI more accessible through an open, collaborative platform.”

Source: company website · checked Sep 5, 2026
13
UBIAIIndirect evidence
Raleigh, NC, United StatesHQ checked Sep 5, 20261-1018

“UbiAI accelerates task-specific model training from months to days.”

Source: company website · checked Sep 5, 2026
14
GriptapeIndirect evidence
Seattle, WA, United StatesHQ checked Sep 5, 202611-5016

“Acquired by Foundry in February 2026.”

Source: company website · checked Sep 5, 2026
15
LangfuseStrong evidence
San Francisco, United StatesHQ checked Sep 5, 202611-5015

“Langfuse is an open source AI engineering platform.”

Source: company website · checked Sep 5, 2026
16
PromptlayerPartial evidence
New York, United StatesHQ checked Sep 5, 202611-5013

“The horizontal AI layer for building, managing, and evaluating prompts, agents, and reusable AI skills across every team and model.”

Source: company website · checked Sep 5, 2026
17
FreeplayIndirect evidence
Boulder, CO, United StatesHQ checked Sep 5, 202611-5010

“A better way to build with LLMs.”

Source: company website · checked Sep 5, 2026
18
BYTEZPartial evidence
San Francisco, CA, United StatesHQ checked Sep 5, 20261-108

“Bytez is the unified platform for AI models and papers.”

Source: company website · checked Sep 5, 2026
19
GENUMPartial evidence
San Francisco, DE, United StatesHQ checked Sep 5, 20261-107

“Crafting the Future of Business Automation with GenAI Genum turns your standart prompts into bulletproof business logic: tested, versioned, and production-ready.”

Source: company website · checked Sep 5, 2026
20
WebvizioIndirect evidence
Pittsburgh, United StatesHQ checked Sep 5, 20261-105

“Webvizio bridges the context gap between non-technical users, developers, and AI coding tools, providing the critical data to solve development tasks on the first try.”

Source: company website · checked Sep 5, 2026
21
Aimon LabsPartial evidence
Palo Alto, CA, United StatesHQ checked Sep 5, 20261-105

“Backed by Bessemer Venture Partners, Tidal Ventures, and other notable angel investors, AIMon is the one platform enterprises need to drive success with AI.”

Source: company website · checked Sep 5, 2026
22
BotdojoPartial evidence
Austin, TX, United StatesHQ checked Sep 5, 20261-104

“BotDojo is a comprehensive platform for designing, testing, and deploying enterprise-level AI solutions.”

Source: company website · checked Sep 5, 2026
23
LangbasePartial evidence
San Francisco, CA, United StatesHQ checked Sep 5, 202611-504

“The complete LLM platform with a superior developer experience and robust infrastructure.”

Source: company website · checked Sep 5, 2026
24
AitechfyIndirect evidence
Cleveland, OH, United StatesHQ checked Sep 5, 20261-104

“Welcome to AITechfy - Your Ultimate Destination for AI Tools!”

Source: company website · checked Sep 5, 2026
25
skydeck.aiPartial evidence
San Jose, CA, United StatesHQ checked Sep 5, 202611-502

“SkyDeck AI is a platform that allows businesses to safely deploy a curated selection of generative AI tools and language models within their organization while being able to…”

Source: company website · checked Sep 5, 2026

Showing 25 of 95 prompt engineering platforms based in the United States

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 1,105 reachable decision-makers.

Free signup · no credit card

See all 95 companies

Prompt engineering platforms based in the United States at a glance

As of Sep 5, 2026
1-10Median size (employees)
San FranciscoLargest hub · 21 HQs
1,109Contacts with mobile numbers
Sep 5, 2026Data refreshed

Companies by employee count

1-10
64
11-50
20
51-200
7
201-500
2
10001+
2

Verified emails by last verification

0–30
1,019
31–60
70
61–90
4
90–180
3
180+
9

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among prompt engineering platforms, so some rows will be adjacent to the category rather than pure plays. The description and evidence rating on every row are there so you can check each match yourself.

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
Companies headquartered in the United States whose own description of what they do matches “prompt engineering platforms”. Matching reads each company's description, not its industry code or its name.
What we exclude
Companies whose own description does not clearly place them among prompt engineering platforms, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
Match quality
In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and an evidence rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
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 listed company carries at least one verified work email, 1,105 across the full list. 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 5, 2026. Lists refresh periodically as the graph is re-checked.
Corrections
Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

How many prompt engineering platforms are there based in the United States?

RevenueBase identified 95 prompt engineering platforms headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Telus Digital AI Data Solutions, headquartered in Las Vegas, tops this list with the largest team on record.

Which city has the most prompt engineering platforms?

San Francisco leads with 21 headquartered companies, followed by New York (5) and Sheridan (4).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 1,105 verified decision-maker contacts tracked across these 95 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 5, 2026.

Ready to reach these companies? Verified emails and direct dials for all 95 prompt engineering platforms based in the United States. Start with a free account, no credit card.

Get the full list

Related lists

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.