Best Web Application Penetration Testing Companies

Web application penetration testing is the most commonly needed form of security testing, and choosing the right provider is critical. The best web app pen testing companies follow OWASP methodologies, test for business logic vulnerabilities that automated scanners miss, and provide actionable remediation guidance.

All providers listed below offer comprehensive web application penetration testing as a core service, with experienced testers who understand modern web frameworks, APIs, and authentication patterns.

31 providers found
31 providers
Top UK ProviderElite TestersResearch-Driven
SECFORCE logo

SECFORCE

Leading UK offensive security consultancy based in Canary Wharf, delivering CREST-accredited penetration testing and adversary simulation to organisations with the most demanding security requirements.

95
Score
LOCLondon, United Kingdom
Web ApplicationNetworkMobile App+9
CRESTISO 27001Cyber Essentials
Best UK ProviderBest for EnterpriseResearch Leaders
NCC Group logo

NCC Group

Global cybersecurity consultancy with CREST, CHECK, and CBEST accreditation, renowned for deep technical research and comprehensive penetration testing services.

75
Score
LOCManchester, United Kingdom
Web ApplicationNetworkMobile App+13
CRESTCHECKCBEST+6
Nettitude logo

Nettitude

CREST, CHECK, and CBEST accredited UK consultancy within Lloyd's Register, delivering premium penetration testing for government and critical infrastructure.

64
Score
LOCLondon, United Kingdom
Web ApplicationNetworkMobile App+10
CRESTCHECKCBEST+2
Best for Mid-MarketBest for Financial Services
NetSPI logo

NetSPI

Leading penetration testing firm with the Resolve platform for continuous attack surface management, trusted by nine of the top ten US banks.

60
Score
LOCMinneapolis, Minnesota, United States
Web ApplicationNetworkCloud+8
SOC 2ISO 27001CREST
Trustwave logo

Trustwave

Global managed security provider with the elite SpiderLabs penetration testing team and deep PCI DSS compliance expertise.

57
Score
LOCChicago, Illinois, United States
Web ApplicationNetworkMobile App+7
PCI QSAISO 27001SOC 2+1
Bridewell logo

Bridewell

Fast-growing CREST and CHECK-accredited UK cybersecurity consultancy with deep expertise in critical national infrastructure sectors.

56
Score
LOCBristol, United Kingdom
Web ApplicationNetworkCloud+7
CRESTCHECKISO 27001+1
Pentest People logo

Pentest People

CREST and CHECK-accredited UK penetration testing firm with an innovative SecurePortal platform and transparent pricing for mid-market organizations.

55
Score
LOCLeeds, United Kingdom
Web ApplicationNetworkMobile App+7
CRESTCHECKCyber Essentials Plus+1
Mandiant logo

Mandiant

World-renowned cybersecurity firm now part of Google Cloud, delivering threat intelligence-led penetration testing and red teaming informed by front-line incident response experience.

53
Score
LOCReston, Virginia, United States
Red TeamingPurple TeamingNetwork+6
SOC 2ISO 27001FedRAMP 3PAO
Best OverallElite TestersResearch Pioneers
Bishop Fox logo

Bishop Fox

Premier US-based offensive security firm known for elite penetration testers, cutting-edge research, and the Cosmos continuous attack surface management platform.

50
Score
LOCTempe, Arizona, United States
Web ApplicationNetworkMobile App+8
SOC 2OSCP Employer
Rapid7 logo

Rapid7

Creators of Metasploit offering enterprise penetration testing integrated with their comprehensive vulnerability management and security operations platform.

50
Score
LOCBoston, Massachusetts, United States
Web ApplicationNetworkMobile App+7
SOC 2ISO 27001
Coalfire logo

Coalfire

Compliance-focused cybersecurity advisory firm and FedRAMP 3PAO specializing in penetration testing that meets stringent regulatory requirements.

50
Score
LOCWestminster, Colorado, United States
Web ApplicationNetworkCloud+5
SOC 2FedRAMP 3PAOPCI QSA+1
WithSecure logo

WithSecure

Leading European cybersecurity firm offering penetration testing with deep expertise in EU regulatory compliance including GDPR, NIS 2, and TIBER-EU.

49
Score
LOCHelsinki, Finland
Web ApplicationNetworkCloud+7
CRESTISO 27001
Claranet logo

Claranet

CREST and CHECK-accredited European managed services provider delivering penetration testing with deep infrastructure and cloud hosting expertise.

48
Score
LOCLondon, United Kingdom
Web ApplicationNetworkMobile App+5
CRESTCHECKISO 27001+1
HackerOne logo

HackerOne

World's largest ethical hacker platform with over one million researchers, offering bug bounties and structured penetration testing to the US DoD and Fortune 500.

47
Score
LOCSan Francisco, California, United States
Web ApplicationAPIMobile App+3
SOC 2ISO 27001FedRAMP 3PAO
Integrity360 logo

Integrity360

CREST-accredited pan-European cybersecurity services provider delivering penetration testing and managed security from Dublin with a strong UK and Ireland presence.

44
Score
LOCDublin, Ireland
Web ApplicationNetworkMobile App+6
CRESTISO 27001SOC 2
Black Hills Information Security logo

Black Hills Information Security

Community-driven penetration testing firm known for free security education, open-source tools, Wild West Hackin' Fest, and practical offensive security services.

44
Score
LOCSpearfish, South Dakota, United States
NetworkWeb ApplicationSocial Engineering+5
SOC 2
SEC Consult logo

SEC Consult

Leading European cybersecurity consultancy from Vienna with a prolific vulnerability research program and deep expertise in IoT and embedded systems security.

43
Score
LOCVienna, Austria
Web ApplicationNetworkMobile App+7
ISO 27001
CrowdStrike logo

CrowdStrike

Global cybersecurity leader leveraging world-class threat intelligence from the Falcon platform to deliver intelligence-led penetration testing and red teaming.

43
Score
LOCAustin, Texas, United States
Red TeamingNetworkWeb Application+5
SOC 2ISO 27001
IOActive logo

IOActive

Elite boutique security consultancy specializing in IoT, SCADA/ICS, embedded systems, and hardware security research with world-renowned researchers.

42
Score
LOCSeattle, Washington, United States
Web ApplicationNetworkIoT+7
OSCP Employer
Secureworks logo

Secureworks

Dell Technologies-backed cybersecurity firm with elite Counter Threat Unit intelligence informing enterprise penetration testing and adversary simulation.

41
Score
LOCAtlanta, Georgia, United States
Web ApplicationNetworkCloud+7
SOC 2ISO 27001
Trail of Bits logo

Trail of Bits

Elite security research firm specializing in source code review, blockchain auditing, and building industry-standard open-source security tools.

41
Score
LOCNew York, New York, United States
Source Code ReviewWeb ApplicationAPI+3
OSCP Employer
Rhino Security Labs logo

Rhino Security Labs

Cloud security penetration testing specialists known for the Pacu AWS exploitation framework and deep expertise across AWS, Azure, and GCP environments.

41
Score
LOCSeattle, Washington, United States
CloudWeb ApplicationNetwork+4
SOC 2
Praetorian logo

Praetorian

Offensive security firm founded by former DoD professionals, offering elite penetration testing and the Chariot continuous attack surface management platform.

40
Score
LOCAustin, Texas, United States
Web ApplicationNetworkCloud+7
SOC 2
Offensive Security logo

Offensive Security

Creators of OSCP, Kali Linux, and Exploit-DB, offering elite penetration testing services from the team that trains the world's ethical hackers.

40
Score
LOCNew York, New York, United States
Web ApplicationNetworkRed Teaming+5
OSCP Employer
Bugcrowd logo

Bugcrowd

Leading crowdsourced security platform offering managed bug bounty programs and crowd-powered penetration testing with hundreds of thousands of ethical hackers.

40
Score
LOCSan Francisco, California, United States
Web ApplicationAPIMobile App+3
SOC 2ISO 27001
Synack logo

Synack

FedRAMP-authorized crowdsourced penetration testing platform combining vetted elite hackers with AI-powered Hydra technology for continuous security testing.

39
Score
LOCRedwood City, California, United States
Web ApplicationNetworkAPI+4
FedRAMP 3PAOSOC 2
Aon Cyber Solutions logo

Aon Cyber Solutions

Cybersecurity consulting division of global insurance leader Aon, uniquely combining penetration testing with cyber risk quantification and insurance expertise.

36
Score
LOCLondon, United Kingdom
Web ApplicationNetworkCloud+5
ISO 27001SOC 2
Securin logo

Securin

Vulnerability intelligence-driven penetration testing firm providing contextual security assessments informed by threat actor exploitation data and ransomware tracking.

34
Score
LOCAlbuquerque, New Mexico, United States
Web ApplicationNetworkAPI+3
SOC 2
BreachLock logo

BreachLock

Cloud-based Penetration Testing as a Service platform combining AI-driven automation with expert manual testing at accessible price points.

33
Score
LOCNew York, New York, United States
Web ApplicationNetworkAPI+4
SOC 2ISO 27001
Cure53 logo

Cure53

Berlin-based specialists in web security, browser security, and cryptographic auditing, trusted by the world's leading VPN providers and privacy tools.

32
Score
LOCBerlin, Germany
Web ApplicationAPISource Code Review+2
Cobalt logo

Cobalt

Pioneer of Pentest as a Service, delivering fast, platform-based penetration testing with a vetted global community of security researchers.

29
Score
LOCSan Francisco, California, United States
Web ApplicationNetworkAPI+2
SOC 2

Best Web Application Penetration Testing Companies — FAQs

How long does a web application pen test take?+

A typical web application pen test takes 5-15 days depending on application complexity, number of user roles, and depth of testing. Large enterprise applications with multiple modules may require longer engagements.

What methodology is used for web app pen testing?+

Most providers follow the OWASP Testing Guide and OWASP ASVS (Application Security Verification Standard). Testing covers the OWASP Top 10 plus business logic flaws, authentication issues, and application-specific risks.

Should I pen test my APIs separately?+

If your web application has a significant API layer (REST, GraphQL), dedicated API testing provides deeper coverage. Many providers offer combined web app and API testing engagements for comprehensive coverage.