Explorium vs Apollo.io vs Semrush

Objective, side-by-side analysis of Explorium, Apollo.io, and Semrush 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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Apollo.io

4.7

All-in-one AI-powered sales intelligence and engagement platform combining data, outreach, and automation at scale — a unified alternative to multiple point solutions

  • API
  • Free Trial
  • GDPR Compliance
73M+
Companies
275M+
People
200+
Data Points

Selected Customers

Autodesk • DocuSign • Customer.io • Census

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Semrush

4.5

The all-in-one platform for online visibility management and competitive digital intelligence

  • API
  • Free Trial
  • GDPR Compliance

Selected Customers

Square • AutoScout24 • Samsung • Amazon • Tesla

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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

Apollo.io

  • AI-Powered Prospecting

    Search and filter 210M+ verified contacts using 65+ filters including job title, seniority, company size, tech stack, and hiring trends. AI identifies and prioritizes best-fit prospects automatically.

  • Multichannel Sales Engagement

    Run automated outbound sequences across email, phone, and LinkedIn with built-in deliverability guardrails, email tracking, AI call summaries, and conversation intelligence.

  • Data Enrichment & Lead Routing

    Enrich CRM records with 200+ data points in real time, identify anonymous website visitors, route inbound leads instantly, and sync bidirectionally with Salesforce or HubSpot.

Signals powering these use cases

  • Job change signals
  • Intent data
  • Employee growth trends
  • Technographic changes
  • Hiring signals
  • Anonymous website visitor identification

Semrush

  • SEO & Keyword Intelligence

    Access 27 billion keywords and track position rankings across 130+ countries with daily updates, enabling teams to build data-driven content strategies and outrank competitors.

  • Competitive Research

    Analyze competitor traffic sources, ad strategies, backlink profiles, and organic rankings to uncover growth opportunities and benchmark performance.

  • Digital Advertising Intelligence

    Monitor rival PPC campaigns, ad creatives, and spend patterns across search and social channels to optimize paid media strategy and reduce wasted budget.

Signals powering these use cases

  • Keyword ranking changes
  • Competitor traffic shifts
  • Backlink gains and losses
  • Ad spend movements
  • Content gap opportunities

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

Apollo.io Snapshot

  • Company coverage 2.1
  • Signals depth 3.5
  • Freshness 3.5

Semrush Snapshot

  • Company coverage 4.5
  • Signals depth 2.3
  • Freshness 3.8

Detailed Feature Comparison

Side-by-side analysis of Explorium, Apollo.io, and Semrush across data coverage, platform capabilities, and technical specifications.

Feature Comparison
Explorium
Apollo.io
Semrush
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
REST API on all plans; 50–200 calls/min by tier; docs at docs.apollo.io
Available on Business and Enterprise plans; also sold as add-on
SLA
Up to 99.999% uptime; rate limit 200 requests/min per key
24-hour RTO/RPO; quarterly audits; annual third-party penetration testing
Enterprise SLA available on custom plans
Compliance
GDPR, SOC 2, CCPA, ISO 27001
GDPR, SOC 2 Type II, ISO/IEC 27001, CCPA; CASA compliant
GDPR, CCPA, PCI DSS Level 1, SOC 2 Type 2
Custom Entities
-
-
Real-time Lookups
Global Coverage
150M+ companies and 800M+ contacts across 150+ countries
210M+ contacts globally; strongest in North America
190+ regions, 130+ countries for rank tracking
CRM Integration
Available on custom enterprise plans
Bidirectional sync with Salesforce, HubSpot, Zoho; bulk invite and field mapping supported
Google Analytics, Search Console; enterprise CRM integrations via API
Platform interface
REST JSON API, MCP server (AgentSource MCP), batch support up to 100 entities, webhooks, sync and async modes
Web application (SaaS), Chrome extension for LinkedIn prospecting, REST API
Web application with dashboards, reporting, and project management
Natural language search
Workflow automation
Automation integrations
n8n, Claude, custom webhook integrations
Zapier, Intercom, Zendesk, ServiceNow, Klaviyo, Salesloft, Outreach
Zapier, API-based custom integrations
Company coverage
150M+ company profiles
30M+ company profiles
43 trillion backlinks indexed; coverage across 190 regions
People coverage
800M+ people profiles (767M+ verified contacts)
210M+ contact records
-
Geographic coverage
150+ countries
Global; strongest in North America; international accuracy lower outside the US
190+ regions globally
Data sources type
50+ data providers; proprietary ML enrichment; real-time web signals
Proprietary 2M+ contributor network, public web crawling, engagement suite signals, vetted third-party data providers
Web crawlers, clickstream data, search engine data, social media APIs
Global schema consistency
Unified schema across 4,000+ data points globally; consistent API response structure
Consistent schema with 65+ filters and 200+ fields globally; accuracy varies by region
Consistent data schema across all 190 tracked regions
Refresh frequency
Daily for high-velocity signals; weekly for semi-dynamic attributes; monthly/quarterly for stable firmographics
Real-time when data signal captured; 150M contacts refreshed monthly; 72M emails verified monthly
Daily updates for rank tracking; near-real-time for alerts
Business enrichments
Company size, revenue, industry, tech stack, funding stage, headcount trends, competitive landscape, website traffic
Company size, revenue, industry, technology stack, funding stage, hiring trends, employee count growth
Traffic analytics, domain authority, competitor benchmarking, market share
Prospect enrichments
Job title, seniority, verified email, phone, LinkedIn URL, job history, people events
Job title, seniority, direct email, mobile phone, LinkedIn URL, job history, social profiles
-
Enrichment categories
Firmographics, technographics, intent, funding, events, contact, website signals, lookalikes
Firmographics, technographics, demographics, intent data, hiring/growth signals, email verification, direct dials
SEO metrics, PPC data, social media analytics, content performance, backlink profiles
Intent data
Event signals
Company events (20+ types), people events (5+ types), funding rounds, acquisitions, hiring surges
Job changes, hiring signals, intent signals, anonymous website visitor activity
Keyword ranking changes, backlink gains/losses, competitor traffic shifts
Technographics
Hiring and growth signals
Matching precision
98% company accuracy; 95% people accuracy
91% stated email accuracy rate; multi-source matching across contributor network and public data
Domain-level and keyword-level matching
Confidence scoring
-
Validation methodology
Advanced ML-based deduplication; 98%+ company accuracy; 95% people accuracy
Proprietary 7-step email verification; real-time verification for bounces; network of 2M+ data contributors
Proprietary web crawlers, clickstream data partnerships, search engine integrations
Deduplication logic
Advanced ML-based deduplication across 50+ data providers
CRM deduplication via native Salesforce and HubSpot sync with bidirectional updates
Domain deduplication across 43T+ backlink database
API availability
QPS performance
Up to 100 QPS; 200 requests/min per API key
200 API calls/min on paid plans; 50 calls/min on free plan
-
CRM integrations
Custom plan — CRM integrations available
Salesforce, HubSpot, Zoho CRM (bidirectional sync)
Google Analytics, Google Search Console, Google Business Profile
Data warehouse support
Custom plan — warehouse ingestion available
CSV export available; direct warehouse connectors not prominently advertised
Custom enterprise integrations available
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
ISO/IEC 27001
-
SLA uptime
Up to 99.999% uptime SLA
24-hour maximum RTO and RPO; quarterly security audits; annual penetration testing
-
Pricing model
Usage-based API credits with custom enterprise plans
Per-seat subscription with tiered credit system for data exports
Per-seat tiered subscription
Credit system
Credit-based; 100 credits on free trial; self-serve and custom plans scale with volume
Credits consumed on contact/company exports and data syncs; Free: 50/month; paid plans scale with tier
Credits apply to on-demand reports and exports depending on plan tier
Tier structure
Free trial, Self-serve, Custom Enterprise
Free, Basic ($49/mo), Professional ($99/mo), Enterprise (custom)
Pro ($117.33/mo annual), Guru ($249.95/mo), Business ($416.66/mo annual), Enterprise (custom)
Free trial details
30-day free trial with 100 credits; covers API and MCP access
Permanent free plan with 50 export credits and 5 mobile credits per month; nearly all features available
7-day free trial on SEO toolkit plans; 14-day trial on Semrush One suite
Budget commitment options
Custom enterprise plans with volume negotiation
Monthly or annual; enterprise volume negotiation available
Monthly or annual commitment; annual billing discounts available
Custom plans available
Bulk deals support
Resell rights
-
-
-

Pricing

Compare pricing models, flexibility, and commitment structure.

Pricing Dimension
Explorium
Apollo.io
Semrush
Pricing Model
Usage-based with custom enterprise plans
Per-seat subscription with credit-based data export limits
Per-seat tiered subscription
Commitment Structure
One-time or custom; no mandatory annual lock-in on self-serve
Monthly or annual; annual plans offered at a discount
Monthly or annual; annual saves 17%
Payment Recurrence
One-time or custom
Monthly or annual
Monthly or Annual
Free Trial
30-day free trial with 100 credits; no credit card required
Free plan with 50 export credits and 5 mobile credits per month; no time limit
7-day free trial on most toolkits; 14-day free trial on Semrush One
Enterprise Customization
Yes — custom plans include CRM integrations, warehouse ingestion, resell rights, and dedicated support
Yes — custom pricing, higher API rate limits, dedicated support, advanced compliance
Custom pricing with dedicated account management, API access, and custom integrations
Onboarding Model
Self-serve for API and MCP; dedicated onboarding for enterprise custom plans
Self-serve for Free/Basic/Professional; dedicated onboarding for Enterprise
Self-serve with documentation; enterprise plans include dedicated 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 Professional

"Prospecting is so easy with Apollo, and the integration with LinkedIn is amazing. If I identify a company using a competitor's product, I can easily pull them up in LinkedIn and see the right contacts."
Verified User for Apollo.io
V

Verified G2 Reviewer

Marketing Manager

"What keeps me coming back is the rabbit hole it lets you go down — and the number of features is exactly what makes that rabbit hole so deep. I'll start by checking one keyword and two hours later I've mapped out an entire content strategy using tools I didn't even know Semrush had."
Verified User for Semrush

Frequently Asked Questions

Is Apollo.io better than Semrush?

It depends on your use case. Apollo.io All-in-one AI-powered sales intelligence and engagement platform combining data, outreach, and automation at scale — a unified alternative to multiple point solutions Semrush The all-in-one platform for online visibility management and competitive digital intelligence

What is the difference between Apollo.io and Semrush?

See the feature-by-feature comparison above. In short: Apollo.io focuses on All-in-one AI-powered sales intelligence and engagement platform combining data, outreach, and automation at scale — a unified alternative to multiple point solutions while Semrush focuses on The all-in-one platform for online visibility management and competitive digital intelligence.

How much does Apollo.io cost compared to Semrush?

Apollo.io pricing model: Per-seat subscription with credit-based exports. Semrush pricing model: Per-seat subscription.

Is Apollo.io or Semrush 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 Apollo.io?

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 Apollo.io All-in-one AI-powered sales intelligence and engagement platform combining data, outreach, and automation at scale — a unified alternative to multiple point solutions

What is the difference between Explorium and Apollo.io?

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 Apollo.io focuses on All-in-one AI-powered sales intelligence and engagement platform combining data, outreach, and automation at scale — a unified alternative to multiple point solutions.

How much does Explorium cost compared to Apollo.io?

Explorium pricing model: Usage-based with custom plans. Apollo.io pricing model: Per-seat subscription with credit-based exports.

Is Explorium or Apollo.io 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 Semrush?

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 Semrush The all-in-one platform for online visibility management and competitive digital intelligence

What is the difference between Explorium and Semrush?

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 Semrush focuses on The all-in-one platform for online visibility management and competitive digital intelligence.

How much does Explorium cost compared to Semrush?

Explorium pricing model: Usage-based with custom plans. Semrush pricing model: Per-seat subscription.

Is Explorium or Semrush 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 accurate is Apollo.io's contact data?

Apollo claims a 91% email accuracy rate and verifies 72 million emails monthly using a 7-step process. 150 million contacts refresh monthly. Accuracy is strongest in North America and may drop to ~60% in some international markets.

Does Apollo.io offer API access?

Yes. Apollo's REST API is available on all plans including free. Free: 50 calls/min; paid plans: 200 calls/min. Enterprise plans can negotiate higher limits. Documentation at docs.apollo.io.

Is Apollo.io GDPR compliant?

Yes. Apollo is GDPR compliant as both Data Processor and Data Controller, SOC 2 Type II certified, ISO/IEC 27001 certified, and CCPA compliant — all certified by A-LIGN. Built-in tools help exclude EU prospects from outreach.

How does Apollo.io's credit system work?

Credits are consumed when exporting contacts to CSV or syncing to a CRM. Free plan: 50 export + 5 mobile credits/month. Basic ($49/mo) and Professional ($99/mo) include higher monthly allotments. Credits do not roll over. Enterprise plans offer custom volumes.

What integrations does Apollo.io support?

Native bidirectional CRM sync with Salesforce, HubSpot, and Zoho. Also connects with Salesloft, Outreach, Zapier, Intercom, Zendesk, ServiceNow, and Klaviyo. Chrome extension enables LinkedIn prospecting. Only one CRM can be connected at a time.

Does Apollo.io have a Claude Code Skill or Claude Plugin?

Yes — Apollo.io offers an official Claude Code plugin. 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.

How does Semrush compare to Ahrefs — which is better for SEO?

Semrush and Ahrefs are the two dominant SEO platforms, and the right choice depends on your primary use case. Semrush leads on keyword data depth (27 billion keywords vs. Ahrefs' roughly 10 billion), PPC intelligence, content tools, and site audit capabilities — making it the stronger all-around choice for agencies and multi-channel marketers. Ahrefs leads on backlink data accuracy and freshness, with the most active web crawler in the industry; its Content Explorer is also considered best-in-class for link building. In 2026, Semrush added AI visibility tracking for ChatGPT and Perplexity citations (via Semrush One), a differentiator Ahrefs has not yet matched.

What are the real costs of adding users to a Semrush plan?

Semrush's base plans only include 1 user seat. Adding extra seats costs $45/month per additional user on all plans. For a 3-person team on Guru ($249.95/month), the actual cost becomes ~$340–$410/month once additional seats are included — a 35–65% increase over the advertised price. Teams evaluating Semrush for multiple users should factor in per-seat costs from the start, as they are not included in the headline pricing.

What are the project and keyword tracking limits per plan?

Semrush enforces project and keyword tracking limits by plan tier. The Pro plan supports 5 projects and tracks 500 keywords. Guru supports 15 projects and 1,500 keywords. Business supports 40 projects and 5,000 keywords. These limits matter for agencies managing multiple client domains or enterprise teams running large-scale tracking campaigns — teams hitting plan limits must upgrade to avoid losing tracking coverage.

What is Semrush One and how is it different from the classic plans?

Semrush One is a newer integrated suite launched alongside the classic Pro/Guru/Business plans, starting at $199/month. It is designed for the AI search era and adds AI visibility tracking (monitoring how brands appear in ChatGPT, Google Gemini, and Perplexity responses), brand monitoring, and a unified cross-channel performance hub. Classic plans focus on traditional SEO, PPC, and backlink tools. Teams concerned about their visibility in AI-generated search results should evaluate Semrush One; teams focused purely on traditional SEO and PPC may not need the additional features at the higher price.

Why does Semrush have a 2.1/5 Trustpilot score despite strong G2 ratings?

Semrush holds a strong 4.5/5 on G2 but only 2.1/5 on Trustpilot — a gap that reflects differences in review audience. G2 reviews come predominantly from active platform users rating features. Trustpilot reviews skew toward billing and cancellation complaints: users report unexpected charges after free trials due to auto-renewal terms, difficulty canceling subscriptions (no direct cancel button in-dashboard — requires contacting support), and refund refusals. Teams should carefully review renewal terms, set calendar reminders before trial expiration, and document cancellation requests if they decide not to continue.

How accurate are Semrush's traffic and keyword volume estimates?

Semrush traffic estimates are modeled approximations — not direct measurements from site analytics. They are generally reliable for directional competitive benchmarking and identifying relative traffic differences between competitors, but actual traffic can differ meaningfully from reported figures, especially for smaller sites with limited clickstream panel coverage. For keyword volume, Semrush is widely regarded as having stronger accuracy than Ahrefs for long-tail and niche keywords, particularly in the US market. Neither platform should be treated as a substitute for first-party data from Google Search Console.

Does Semrush have a Claude Code Skill or Claude Plugin?

Not officially — Semrush 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.