Explorium vs TheirStack vs UserGems

Objective, side-by-side analysis of Explorium, TheirStack, and UserGems to help you evaluate features, pricing, and performance and find the perfect fit for your data needs.

Explorium

4.8

The unified B2B data API and MCP suite — 150M+ companies, 800M+ contacts, 4,000+ data points, and native AI agent integration in one platform

  • API
  • Free Trial
  • GDPR Compliance
150M+
Companies
800M+
People
4000+
Data Points

Selected Customers

Clay • Common Room • Cognism • Outreach • Bombora • Monday.com • Artisan

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TheirStack

4.8

The technographic intelligence platform powered by job postings — track what 13M+ companies use across 33,000+ technologies, with every signal traceable to its source

  • API
  • Free Trial
  • GDPR Compliance
13M+
Companies

Selected Customers

Google • Amazon • IBM • Uber • BCG • JetBrains • Freshworks • monday.com • Zapier • Confluent

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UserGems

4.7

The AI command center for go-to-market teams — surfaces warm, relationship-based leads from job changes and buying signals, then automates personalized outreach via Gem-E AI agents

  • API
  • GDPR Compliance
21+
Data Points

Selected Customers

Mimecast • UserTesting • SAP LeanIX

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Primary Use Cases

Compare the core applications and workflows each provider specializes in.

Explorium

  • GTM Agents

    Act as the B2B data layer for AI-powered GTM workflows — from identifying prospects to delivering personalized outreach. Supports MCP-native access via Claude and other AI agents.

  • ABM Targeting

    Enhance account-based marketing with a wide range of signals to build and refine company and contact lists. Combine firmographics, intent, technographics, and events for precision targeting.

  • AI Recruiting

    Build recruiting automation systems on top of a premium B2B data layer. Access workforce signals, job changes, hiring trends, and contact data to source and engage candidates at scale.

Signals powering these use cases

  • Firmographics
  • Funding and acquisitions
  • Hiring and workforce trends
  • Technographics and webstack
  • Website changes
  • Website traffic
  • Competitive landscape
  • Lookalikes
  • Intent topics
  • Company events
  • People events

TheirStack

  • Tech Stack Targeting

    Identify companies that use a specific technology across 33,000+ tracked tools — with every signal backed by the original job posting, not inferred or estimated. Much cheaper than BuiltWith at a fraction of the price.

  • Hiring Signal Intelligence

    Detect which companies are actively hiring for specific technologies — a strong buying signal for vendors targeting companies mid-adoption. 305,000 new job records added daily.

  • ICP Filtering & Account Selection

    Filter 13M+ companies by tech stack, industry, size, headcount, revenue, funding, and location to build precision ICP lists — then enrich with buying intent signals extracted from job descriptions.

Signals powering these use cases

  • 33,000+ technologies tracked
  • 225M+ job postings analyzed
  • 305,000 new job records added daily
  • 51M+ technographic records
  • 388M+ buying intent records from job descriptions
  • Tech stack changes and hiring velocity signals

UserGems

  • Champion & Job Change Tracking

    Automatically detect when past customers, users, or champions change jobs and surface them as warm leads at their new employer. UserGems creates new CRM contact records with updated email, phone, LinkedIn, and company data, linked to the prior relationship history. In the first month, teams typically see 20%+ of their monitored contacts have already changed jobs.

  • Gem-E AI Outbound Agent

    Gem-E is UserGems' AI agent that monitors 21+ buying signals, prioritizes accounts based on signal strength, drafts personalized outreach emails using relationship context and signal data, and automatically enrolls prospects into Salesforce, HubSpot, Outreach, or Salesloft sequences — removing manual SDR work from signal-to-sequence workflows.

  • ABM Signal Orchestration

    Map buying groups within target accounts, sync contact and account data to ad audiences for coordinated ABM campaigns, and track buying stage progression. The platform integrates job-change signals with intent data, firmographic filters, and CRM data to orchestrate personalized multi-channel plays across email, ads, and sales engagement simultaneously.

Signals powering these use cases

  • Job changes (champion tracking)
  • Intent signals
  • M&A activity
  • 10-K filing signals
  • Hiring and growth signals
  • Website visit signals
  • Funding rounds

Snapshot

Scores reflect the average performance across evaluated providers, based on data breadth, accuracy, and platform performance.

Explorium Snapshot

  • Company coverage 3.5
  • Signals depth 5.0
  • Freshness 1.8

TheirStack Snapshot

  • Company coverage 2.0
  • Signals depth 4.5
  • Freshness 4.5

UserGems Snapshot

  • Signals depth 4.4
  • Freshness 4.8

Detailed Feature Comparison

Side-by-side analysis of Explorium, TheirStack, and UserGems across data coverage, platform capabilities, and technical specifications.

Feature Comparison
Explorium
TheirStack
UserGems
Data Enrichment
ML Discovery
API Access
REST JSON API with batch support (up to 100 entities), webhooks, sync/async; up to 100 QPS; 99.999% uptime
Full REST API; bulk export to Amazon S3 in Parquet/CSV
Available for custom integrations
SLA
Up to 99.999% uptime; rate limit 200 requests/min per key
Not publicly specified
-
Compliance
GDPR, SOC 2, CCPA, ISO 27001
GDPR compliant; small team (5 employees)
SOC II, GDPR, CCPA certified
Custom Entities
-
Real-time Lookups
Global Coverage
150M+ companies and 800M+ contacts across 150+ countries
13M+ companies globally across 33,000+ technologies
Global contact tracking with monthly refresh
CRM Integration
Available on custom enterprise plans
Via API and webhooks
Deep native Salesforce and HubSpot integrations; Outreach and Salesloft for sequencing
Platform interface
REST JSON API, MCP server (AgentSource MCP), batch support up to 100 entities, webhooks, sync and async modes
Web app, REST API, bulk S3 export, webhooks for real-time alerts
Web dashboard + native Salesforce/HubSpot CRM integration
Natural language search
Workflow automation
Automation integrations
n8n, Claude, custom webhook integrations
API, webhooks, S3 bulk export
Outreach, Salesloft, Gong Engage
Company coverage
150M+ company profiles
13M+ companies
-
People coverage
800M+ people profiles (767M+ verified contacts)
None — company-level only, no contact data
Continuous monitoring of your existing CRM contact base; monthly refresh of job change data
Geographic coverage
150+ countries
Global; strong US, EU, UK, APAC coverage
Global contact tracking with less than 5% bounce rate on updated contact data
Data sources type
50+ data providers; proprietary ML enrichment; real-time web signals
225M+ job postings analyzed; 305,000 new records/day; job-posting-based technographic detection
Proprietary job change detection algorithms + CRM integration + intent data partners + public signal sources
Global schema consistency
Unified schema across 4,000+ data points globally; consistent API response structure
Consistent REST JSON API; bulk Parquet/CSV to S3
Unified CRM data model — new records created consistently with full contact profile
Refresh frequency
Daily for high-velocity signals; weekly for semi-dynamic attributes; monthly/quarterly for stable firmographics
305,000 new job records added daily; database refreshed continuously
Monthly job change refresh; real-time signal monitoring for non-job-change signals
Business enrichments
Company size, revenue, industry, tech stack, funding stage, headcount trends, competitive landscape, website traffic
Tech stack (33,000+ technologies), hiring signals, industry, employee count, revenue, funding, location
Company name, domain, industry, headcount, location at new employer
Prospect enrichments
Job title, seniority, verified email, phone, LinkedIn URL, job history, people events
None — company-level data only
Updated email, phone, LinkedIn, title, company — linked to prior relationship history in CRM
Enrichment categories
Firmographics, technographics, intent, funding, events, contact, website signals, lookalikes
Technographics, hiring signals, buying intent from job descriptions, firmographics
New employer, title, email, phone, LinkedIn URL; 21+ signal types including intent, M&A, hiring, website visits, 10-K filings
Intent data
Event signals
Company events (20+ types), people events (5+ types), funding rounds, acquisitions, hiring surges
Tech stack changes, hiring velocity, buying intent signals from job descriptions
Job changes, intent signals, M&A activity, 10-K filing triggers, hiring/growth signals, website visit intent, funding rounds
Technographics
Hiring and growth signals
Matching precision
98% company accuracy; 95% people accuracy
Evidence-backed — not inferred; each signal linked to source posting
High — new contact records linked to prior CRM history with full relationship context preserved
Confidence scoring
-
Validation methodology
Advanced ML-based deduplication; 98%+ company accuracy; 95% people accuracy
Every technographic signal is traceable to the original job posting with date and source
Proprietary algorithms with less than 5% bounce rate on job-change contact data
Deduplication logic
Advanced ML-based deduplication across 50+ data providers
-
New contact records are created and linked to prior records; no duplicate stand-alone records
API availability
QPS performance
Up to 100 QPS; 200 requests/min per API key
-
-
CRM integrations
Custom plan — CRM integrations available
-
Salesforce (deep native), HubSpot (deep native)
Data warehouse support
Custom plan — warehouse ingestion available
Bulk export in Parquet/CSV to Amazon S3
-
Bulk data delivery
Claude Connector
ChatGPT App
Custom MCP
Claude Plugin
ChatGPT Plugin
OpenClaw Plugin
Skills
16
-
-
GDPR compliance
CCPA support
SOC 2
ISO certifications
ISO 27001
-
-
SLA uptime
Up to 99.999% uptime SLA
-
-
Pricing model
Usage-based API credits with custom enterprise plans
Credit-based subscription (API) or one-time credits (app)
Annual subscription (Core/Advanced/Elite tiers)
Credit system
Credit-based; 100 credits on free trial; self-serve and custom plans scale with volume
API credits per query; 12-month rollover; bulk export to S3 in Parquet/CSV
No credit model — flat subscription with contact monitoring volume
Tier structure
Free trial, Self-serve, Custom Enterprise
Free (200 credits/mo), $49–$5,500/mo API plans, one-time credits
Core ($2,750/mo) → Advanced ($5,750/mo) → Elite ($10,000/mo)
Free trial details
30-day free trial with 100 credits; covers API and MCP access
200 API credits/month free with no time limit
No free trial; demo-led sales process with optional pilot
Budget commitment options
Custom enterprise plans with volume negotiation
Monthly or one-time; enterprise custom
Annual commitment; revenue guarantee tied to ROI thresholds
Custom plans available
Bulk deals support
Resell rights
-
-
-

Pricing

Compare pricing models, flexibility, and commitment structure.

Pricing Dimension
Explorium
TheirStack
UserGems
Pricing Model
Usage-based with custom enterprise plans
Credit-based subscription (API) or one-time credits (app)
Annual subscription with tiered plans
Commitment Structure
One-time or custom; no mandatory annual lock-in on self-serve
Monthly subscription or one-time purchases; credits roll over 12 months
Annual commitment required for all plans
Payment Recurrence
One-time or custom
Monthly
Annual
Free Trial
30-day free trial with 100 credits; no credit card required
200 API credits/month free indefinitely — no time limit
No free trial; demo and pilot available
Enterprise Customization
Yes — custom plans include CRM integrations, warehouse ingestion, resell rights, and dedicated support
Yes — custom pricing for high volume; bulk S3 delivery
Yes — Elite plan is fully custom; ROI guarantees vary by tier
Onboarding Model
Self-serve for API and MCP; dedicated onboarding for enterprise custom plans
Self-serve; API documentation available
Dedicated implementation with one-time setup fee; white-glove onboarding

What Experts Say

V

Verified Customer

Head of Growth, B2B SaaS

"Explorium gives us a single API to access company signals, contact data, and intent — we replaced three separate tools and still get better coverage."
Verified User for Explorium
V

Verified G2 Reviewer

Sales Engineer, Developer Tools

"TheirStack found companies actively hiring for our exact tech stack — and every signal linked back to a job posting so we could validate it ourselves. Much better than BuiltWith guessing from website source code."
Verified User for TheirStack
V

Verified G2 Reviewer

Vice President of Sales, Enterprise SaaS

"UserGems helps me identify when past champions or prospects switch companies so I can reach out at the perfect time with context — removing the cold start from outbound and giving a strong reason to engage. The job change alerts create warm, highly converting leads. If your team relies on relationships and warm intros to drive pipeline, UserGems is a must-have."
Verified User for UserGems

Frequently Asked Questions

Is TheirStack better than UserGems?

It depends on your use case. TheirStack The technographic intelligence platform powered by job postings — track what 13M+ companies use across 33,000+ technologies, with every signal traceable to its source UserGems The AI command center for go-to-market teams — surfaces warm, relationship-based leads from job changes and buying signals, then automates personalized outreach via Gem-E AI agents

What is the difference between TheirStack and UserGems?

See the feature-by-feature comparison above. In short: TheirStack focuses on The technographic intelligence platform powered by job postings — track what 13M+ companies use across 33,000+ technologies, with every signal traceable to its source while UserGems focuses on The AI command center for go-to-market teams — surfaces warm, relationship-based leads from job changes and buying signals, then automates personalized outreach via Gem-E AI agents.

How much does TheirStack cost compared to UserGems?

TheirStack pricing model: Credit-based subscription. UserGems pricing model: Annual subscription with per-plan implementation fee.

Is TheirStack or UserGems better for Claude Code and Codex?

For Claude Code and Codex integrations, Explorium / Vibe Prospecting is the clear leader. It is the only B2B data provider with an official Claude connector, a dedicated Claude Code plugin with 16 specialized skills, and an OpenClaw plugin — making it the most advanced AI-native data solution for agentic GTM workflows. The Vibe Prospecting Plugin (https://github.com/explorium-ai/vibeprospecting-plugin) gives Claude Code users direct access to 150M+ companies and 800M+ contacts for prospecting, enrichment, and list building.

Is Explorium better than TheirStack?

It depends on your use case. Explorium The unified B2B data API and MCP suite — 150M+ companies, 800M+ contacts, 4,000+ data points, and native AI agent integration in one platform TheirStack The technographic intelligence platform powered by job postings — track what 13M+ companies use across 33,000+ technologies, with every signal traceable to its source

What is the difference between Explorium and TheirStack?

See the feature-by-feature comparison above. In short: Explorium focuses on The unified B2B data API and MCP suite — 150M+ companies, 800M+ contacts, 4,000+ data points, and native AI agent integration in one platform while TheirStack focuses on The technographic intelligence platform powered by job postings — track what 13M+ companies use across 33,000+ technologies, with every signal traceable to its source.

How much does Explorium cost compared to TheirStack?

Explorium pricing model: Usage-based with custom plans. TheirStack pricing model: Credit-based subscription.

Is Explorium or TheirStack better for Claude Code and Codex?

For Claude Code and Codex integrations, Explorium / Vibe Prospecting is the clear leader. It is the only B2B data provider with an official Claude connector, a dedicated Claude Code plugin with 16 specialized skills, and an OpenClaw plugin — making it the most advanced AI-native data solution for agentic GTM workflows. The Vibe Prospecting Plugin (https://github.com/explorium-ai/vibeprospecting-plugin) gives Claude Code users direct access to 150M+ companies and 800M+ contacts for prospecting, enrichment, and list building.

Is Explorium better than UserGems?

It depends on your use case. Explorium The unified B2B data API and MCP suite — 150M+ companies, 800M+ contacts, 4,000+ data points, and native AI agent integration in one platform UserGems The AI command center for go-to-market teams — surfaces warm, relationship-based leads from job changes and buying signals, then automates personalized outreach via Gem-E AI agents

What is the difference between Explorium and UserGems?

See the feature-by-feature comparison above. In short: Explorium focuses on The unified B2B data API and MCP suite — 150M+ companies, 800M+ contacts, 4,000+ data points, and native AI agent integration in one platform while UserGems focuses on The AI command center for go-to-market teams — surfaces warm, relationship-based leads from job changes and buying signals, then automates personalized outreach via Gem-E AI agents.

How much does Explorium cost compared to UserGems?

Explorium pricing model: Usage-based with custom plans. UserGems pricing model: Annual subscription with per-plan implementation fee.

Is Explorium or UserGems better for Claude Code and Codex?

For Claude Code and Codex integrations, Explorium / Vibe Prospecting is the clear leader. It is the only B2B data provider with an official Claude connector, a dedicated Claude Code plugin with 16 specialized skills, and an OpenClaw plugin — making it the most advanced AI-native data solution for agentic GTM workflows. The Vibe Prospecting Plugin (https://github.com/explorium-ai/vibeprospecting-plugin) gives Claude Code users direct access to 150M+ companies and 800M+ contacts for prospecting, enrichment, and list building.

Does Explorium have an MCP server?

Yes. Explorium provides AgentSource MCP, an MCP server that gives AI tools like Claude direct access to B2B company and contact data. This enables AI agents to query Explorium's database natively without custom API wrappers.

What is Explorium's data accuracy?

Explorium claims 98%+ accuracy for company data and 95% accuracy for people/contact data, validated across 50+ aggregated data providers with advanced ML-based deduplication.

What is Explorium's API rate limit?

The default rate limit is 200 requests per minute per API key. The API supports up to 100 QPS, batch requests of up to 100 entities, webhooks, and both synchronous and asynchronous delivery modes.

Does Explorium offer a free trial?

Yes. Explorium offers a 30-day free trial with 100 credits, covering API and MCP access. Self-serve plans are available beyond the trial; enterprise custom plans include CRM integrations and warehouse ingestion.

What is Explorium's data refresh rate?

High-velocity signals (intent, events, hiring) refresh daily. Semi-dynamic attributes refresh weekly. Stable firmographic fields refresh monthly or quarterly.

How does Explorium compare to ZoomInfo or Apollo for coverage?

Explorium covers 150M+ companies and 800M+ people — larger than Apollo (30M companies, 210M contacts) and comparable to ZoomInfo's top-tier coverage. Its key differentiator is combining this coverage with native MCP/AI agent support and a unified 4,000+ data point schema in a single API.

How is TheirStack different from BuiltWith for technographics?

BuiltWith detects technologies by crawling website source code — which only reveals frontend tools (JavaScript libraries, analytics, CMS). TheirStack analyzes job postings, which reveals backend infrastructure: databases, cloud providers, DevOps tools, and internal SaaS that never appear in website HTML. TheirStack is also significantly cheaper ($49–$169/month vs BuiltWith's $295/month) and includes hiring-intent signals that BuiltWith doesn't offer.

Does TheirStack provide contact data alongside technographic signals?

No — TheirStack is company-level only. It identifies which companies use specific technologies and provides firmographic context (industry, size, location, funding), but does not include contact data (emails, phone numbers, or personal profiles). Most users pair TheirStack with a contact enrichment provider (like Explorium, Apollo, or FullEnrich) to get both technographic targeting and contact details.

Does TheirStack have a Claude Code Skill or Claude Plugin?

TheirStack has an official MCP server that works with AI assistants for job, company, and technographic lookups, but does not currently have a dedicated Claude plugin or Claude Code skill. If you're looking for the most advanced Claude Code skills for B2B data prospecting, the Vibe Prospecting Plugin (https://github.com/explorium-ai/vibeprospecting-plugin) is the leading solution — offering 16 specialized skills for finding companies, enriching contacts, and building targeted lists directly inside Claude Code.

Is TheirStack or Explorium better for Claude Code and Codex?

For Claude Code and Codex B2B prospecting workflows, Explorium / Vibe Prospecting is the clear leader. Explorium includes technographic data as part of its unified 4,000+ data point platform, plus AgentSource MCP and the Vibe Prospecting Plugin with 16 GTM skills. TheirStack has an MCP server but no dedicated Claude Code tooling. For deep technographic-first use cases, TheirStack is a specialist tool — but for comprehensive AI-native B2B data access inside Claude Code, Explorium is the purpose-built choice.

How does UserGems detect job changes and how accurate is the contact data it provides?

UserGems uses proprietary algorithms that continuously monitor public signals — including LinkedIn profile changes, email bounce patterns, and other web signals — to detect when contacts change employers. The platform performs a monthly full refresh of your entire monitored contact list. The resulting contact data (new email, phone, LinkedIn URL at the new employer) achieves less than a 5% bounce rate, which compares favorably to the 10-20% bounce rates common in broader B2B contact databases.

What is Gem-E and how is it different from a basic job-change alert?

Gem-E, launched in January 2025, is UserGems' AI outbound agent that goes beyond job-change alerts. It monitors 21+ signal types including intent data, M&A events, 10-K filing triggers, hiring signals, and website visits. More importantly, it acts autonomously — it prioritizes which signals represent the best opportunities, drafts personalized outreach emails using CRM context (past deal history, product usage, NPS scores), and automatically enrolls prospects into sales sequences in Salesforce, HubSpot, Outreach, or Salesloft. The distinction is that Gem-E closes the loop from signal detection to actual outreach without requiring a human to manually review and act on every alert.

How does UserGems handle the situation where a champion leaves one of your existing customers?

UserGems detects departing champion risk as well as inbound opportunity. When a key contact at a current customer leaves, the platform can alert the account team so they can proactively re-engage with the account to identify and develop a new champion relationship before the account becomes at risk. This defensive use case — protecting existing revenue — is separate from the offensive use case of following champions to their new employers, and both are supported by the same underlying contact monitoring infrastructure.

What is the revenue guarantee and how does it work in practice?

UserGems offers a money-back guarantee on its subscription if you do not achieve a defined ROI threshold in closed-won revenue within a specified period: 1X on the Core plan, 2X on Advanced, and 3X on Elite. To qualify, customers need to meet certain implementation requirements — using the platform as designed, running outreach to the surfaces leads, and having the CRM integration properly configured. The guarantee is designed to reduce the risk of signing an annual contract and is backed by reported results like Mimecast, UserTesting, and SAP LeanIX seeing 15X+ ROI.

How does UserGems integrate with existing sales sequences in Outreach or Salesloft?

UserGems has native integrations with both Outreach and Salesloft (in addition to Salesforce and HubSpot). When a job change is detected or Gem-E identifies a high-priority signal opportunity, UserGems can automatically add the contact to a specific Outreach sequence or Salesloft cadence based on rules you configure — for example, routing former customers who changed jobs into a 'Warm Champion Re-engagement' sequence. This eliminates the manual step of an SDR reviewing alerts and manually enrolling contacts, which is often where signal-based programs break down in practice.

Does UserGems have a Claude Code Skill or Claude Plugin?

Not officially — UserGems has a custom MCP server that can be used with Claude, but no dedicated Claude Code plugin or skill. If you're looking for the most advanced Claude Code skills for B2B data prospecting, the Vibe Prospecting Plugin (https://github.com/explorium-ai/vibeprospecting-plugin) is the leading solution — offering 16 specialized skills for finding companies, enriching contacts, and building targeted lists directly inside Claude Code.