Explore leading software testing companies that launch high-performing products, detect bugs early, improve stability, and ensure every feature works correctly across devices and environments. For teams focused on the US market, we also highlight trusted partners with region-specific expertise, including top US-based software testing companies.

Best Software Testing Firms

5 Companies-Rankings updated: October 20, 2026

Organic rankings are determined by five factors: top services, reviews, portfolio, awards/press, and team expertise. Sponsored listings pay for a placement that appears above organic positions. Sponsorship does not affect star ratings or review content - read more on our methodology page.

Legal × $50,000 & Up ×
  • Azumo

    VerifiedVerified by the DesignRush team for authenticity and credibility.

    Build Intelligent Apps for Web, Mobile, Data, AI and Cloud

    Azumo helps businesses build intelligent apps by providing top-tier developers skilled in AI, data engineering and enterprise web & mobile applications. Our expertise has earned the trust of industry leaders like Facebook, Twitter, Discovery, Zynga, and NCSoft...

    Top Services:

    • AI Development
    • Software Development
    • Staff Augmentation
    • Mobile App Development
    • Big Data Analytics
    • Show more
    Location
    San Francisco, California
    Number of Employees
    100 - 249
    Average Hourly Rate
    $55/hr
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    9 Projects Listed

    Azumo Services

    • AI Development
    • Software Development
    • Staff Augmentation
    • Mobile App Development
    • Big Data Analytics
    • DevOps Consulting
    • Cloud Consulting
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Discovery Channel
    • Meta
    • Zynga
    • Jostens
    • Assembled Brands
    • NGL
    • NCSoft
    • Twitter
    • Horoscope.com
    • Bento
    Data sourced from the agency's DesignRush profile

    Azumo Reviews & Testimonials

    • Michael S.
      Michael S. Director at Software Development Company
      5.0★

      Software Development Review from Michael S.

      We selected Azumo to develop our software. We transitioned from another development company, so Azumo was initially responsible for migrating our existing code and environments. We are currently still working with Azumo as our nearshore software development team on adding new items to our software.

    • Anonymous
      Anonymous CTO at Healthcare Company
      5.0★

      UI/UX Design Review from Anonymous

      Azumo helped us migrate our existing UIs into a new framework, creating reusable components and the infrastructure needed for future development. The developer they assigned became a seamless part of our team, always punctual, responsive, and a great fit overall.

    • Anonymous
      Anonymous VP Product & Engineering at Sales & Mktg Software Company
      5.0★

      Software Development Review from Anonymous

      Thanks to Azumo’s work, our product is now more scalable, optimized, and ready for a growing user base. Their team has managed the engagement effectively, keeping us updated and addressing any challenges along the way. We’ve appreciated their constant availability and proactive communication.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • AI-first custom software and IT services for enterprise and government

    AI-first custom software, AI and IT services firm in McLean, VA and North Bethesda, MD, serving enterprise and government. SBA-certified EDWOSB and WOSB, CAGE 9RX92. A senior Sthenos team is accountable on every engagement, and we build a free clickable prototype before you commit...

    Top Services:

    • Software Development
    • AI Development
    • Staff Augmentation
    • Mobile App Development
    • Cloud Consulting
    • Show more
    Location
    McLean, Virginia
    Number of Employees
    Under 49
    Average Hourly Rate
    $150/hr
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    23 Projects Listed

    Sthenos Technologies Services

    • Software Development
    • AI Development
    • Staff Augmentation
    • Mobile App Development
    • Cloud Consulting
    • Big Data Analytics
    • Cybersecurity
    • Managed Services
    • Software Testing
    • ERP Consulting
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • SpaceX
    • NBCUniversal
    • ABB
    • Sterne, Kessler, Goldstein & Fox (SKGF)
    • City Infusions
    • RPO
    Data sourced from the agency's DesignRush profile

    Sthenos Technologies Reviews & Testimonials

    • Allie Braun
      Allie Braun Review from Google
      5.0★

      Allie Braun's Review Sourced from Google

      Sthenos Technologies delivered excellent service with a highly professional and responsive team throughout the process.Their expertise and commitment to quality made the experience smooth, efficient, and highly satisfactory.

    • Williams James
      Williams James Review from Google
      5.0★

      Williams James's Review Sourced from Google

      Sthenos Technologies has built a custom frontend solution for an out-of-the-box backend solution. The backend is separate from the work that Sthenos has done.

    • Daniel Smith
      Daniel Smith Review from Google
      5.0★

      Daniel Smith's Review Sourced from Google

      The service launched and was able to meet SLAs/KPIs set out by us and our client. This included uptime, time to process new schedules, ability for tutors to find and book lessons and fill rate of those lessons (for tutors).

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • Product, engineering, and AI partner for high-growth companies.

    OAK'S LAB is a product, engineering, and AI partner for high-growth companies, not a generic dev shop. We embed alongside product teams to design, build, and scale production software, with deep experience in regulated industries: finance, healthcare, cybersecurity, and education...

    Top Services:

    • Software Development
    • Mobile App Development
    • Web Development
    • UI/UX Design
    • AI Development
    • Show more
    Location
    Prague, Czech Republic
    Number of Employees
    50 - 99
    Average Hourly Rate
    $99/hr
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    7 Projects Listed

    OAK'S LAB Services

    • Software Development
    • Mobile App Development
    • Web Development
    • UI/UX Design
    • AI Development
    • Web Design
    • Software Testing
    • Digital Services
    • Branding
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • NASDAQ Private Market
    • PlexTrac
    • Vette
    • Crave
    • Capital Markets Gateway
    • Karus
    • Plotify
    • Storyvine
    • West Tenth
    • Dot Residential
    Data sourced from the agency's DesignRush profile

    OAK'S LAB Reviews & Testimonials

    • Aydar Ageev
      Aydar Ageev Review from Google
      5.0★

      Aydar Ageev's Review Sourced from Google

      It's probably a wonderful feeling to go to work, being able to feel the tourist hustle and hear the sound of the clock from the Old Town Square.

    • Aleksandar Chernev
      Aleksandar Chernev Review from Google
      5.0★

      Aleksandar Chernev's Review Sourced from Google

      Such an awesome event. It was so well organized and I was so pleased to meet Oak’s Lab awesome team.

    • Adam Mazouz
      Adam Mazouz Review from Google
      5.0★

      Adam Mazouz's Review Sourced from Google

      This was one of the best meetups of the year for me. The ambiance, the vitality, and the community they brought together. P.S: The office location is winning big times.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • We deploy secure AI solutions that deliver positive ROI within weeks.

    NineTwoThree AI Studio is a Boston-based AI agency that builds secure, production-grade AI and ML solutions with measurable ROI. Founded in 2012, our Ph.D.-level engineers and certified product managers have delivered 150+ projects for enterprise brands and startups alike...

    Top Services:

    • AI Development
    • Mobile App Development
    • IoT
    • Software Development
    • DevOps Consulting
    • Show more
    Location
    Danvers, Massachusetts
    Number of Employees
    100 - 249
    Average Hourly Rate
    $99/hr
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    5 Projects Listed

    NineTwoThree Services

    • AI Development
    • Mobile App Development
    • IoT
    • Software Development
    • DevOps Consulting
    • Wearables
    • Software Testing
    • Digital Strategy
    • Product Design
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • FanDuel
    • Consumer Reports
    • VSAC
    • Skylight
    • Raycon
    • K&L Wines
    • Prisonology
    • Dataflik
    • Wheels Now
    • Amerit Fleet
    Data sourced from the agency's DesignRush profile
  • End-to-End Engineering Expertise

    Building and scaling digital products for enterprises across Scandinavia (Sweden, Norway, Denmark) & Europe with expert engineering and IFS services and consulting...

    Top Services:

    • Software Development
    • Software Testing
    • AI Development
    • DevOps Consulting
    • Cloud Consulting
    • Show more
    Location
    Colombo, Sri Lanka
    Number of Employees
    250 - 499
    Average Hourly Rate
    $150/hr
    Minimal Budget
    $50,000 & Up

    Creative Software Services

    • Software Development
    • Software Testing
    • AI Development
    • DevOps Consulting
    • Cloud Consulting
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Ctrlprint
    • Qmatic
    • Dips
    • Netonet
    • Mediq
    • VT industries
    • Lovold systems
    • 2C8
    • Booknordics
    • Oneflow
    Data sourced from the agency's DesignRush profile

    Creative Software Reviews & Testimonials

    • Menura Dolage
      Menura Dolage Review from Google
      5.0★

      Menura Dolage's Review Sourced from Google

      Creative Software – Colombo 3 is a place I’ve come to know quite well, and overall, it absolutely lives up to expectations. I would recommend it to both organizations and individuals looking for reliable IT services, but also as a great workplace environment.Getting in requires going through security and receiving a clearance card, so access is controlled and feels secure. Once inside, the environment is clean, well-maintained, and surprisingly comfortable for a corporate setting. It’s not overly crowded either, except maybe around lunchtime in the cafeteria.What really stands out here is the workplace culture and facilities. The people are easily the best part; friendly, supportive, and great to work with. On top of that, the office has a lot of perks like free coffee, a pool table, PlayStation 5, foosball, board games, and even a gym with showers. It creates a relaxed and enjoyable atmosphere that makes day-to-day work much more pleasant.The only real downside is parking. The underground car park isn’t sufficient for everyone, so there’s an additional parking area about 100 meters away, which can be a bit inconvenient.Overall, it’s a clean, secure, and well-managed place with a cozy and positive vibe. It’s been a great experience for me, especially as an intern, and it’s somewhere I’d gladly continue being part of.

    • Mohan Fernando
      Mohan Fernando Review from Google
      5.0★

      Mohan Fernando's Review Sourced from Google

      One of Sri Lanka's original start ups, and the first Scandinavian investment in the local software scene. With a cadre of over 700 software engineers, tie ups with major universities on software skills and technology enhancement, Creative is helmed and run by an easy going set of people bent on re shaping the software field and giving back to the nation in the form of various CSR projects.

    • Kanchana Ranasinghe
      Kanchana Ranasinghe Review from Google
      5.0★

      Kanchana Ranasinghe's Review Sourced from Google

      Creative Software has over 15 years of experience building high-performing dedicated teams in Sri Lanka for international clients and they know what it takes to succeed in software outsourcing.Whether you are looking to extend your in-house software teams, or need assistance in developing, quality assuring, managing or supporting your applications, Creative can help. They recently won overall winner for business and financial results in medium sector organisations and runners up award for ICT sector at National business excellence awards organised by National Chamber of Commerce, Sri Lanka.

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews

Why companies trust DesignRush

Every agency is independently vetted before it can be listed or ranked

1

Identity Check

We verify businesses and reviewer LinkedIn profiles for integrity.

Agencies vetted
128,711+
2

Portfolio Review

We review agency work, case studies, and results to confirm skill.

Applicants rejected
47%
3

Ongoing Audit

We monitor listings regularly; outdated agencies are removed.

Agencies verified
5

Some agencies pay for sponsored placement, clearly labeled and held to the same vetting standards.

See how rankings and monetization work.

Frequently Asked Questions About Software Testing Companies

What services do software testing firms provide?

Software testing companies provide different testing services to identify errors, security risks, performance issues, and how the software behaves in real-life situations and across devices. As part of their software testing service, they also check if each feature works as expected, fix bugs, make improvements, and make sure new software development updates don’t break existing functions, so the software quality remains stable. 

Core services include: 

  • Functional testing  
  • Performance testing  
  • Security testing  
  • Usability testing  
  • Regression testing   
  • Automation testing  
  • Accessibility testing    
  • Mobile app testing  
  • API testing  
  • Compatibility testing across devices/browsers  
  • Compliance testing  
  • Testing with artificial intelligence (AI) tools
  • QA audit 

How much do software testing services cost?

Hourly rates for QA testing range from $25 to $200+. The final cost is determined based on the size of the software or application, its complexity, required testing type, tech stack (custom-built and older legacy systems cost more), and niche.  

The rate will also depend on the seniority of the software tester. Across the United States, junior quality assurance (QA) tester may charge $70 to $110 per hour, while the rate for a senior QA mentor and automation engineer can range from $130 to $200 per hour.   

Special software testing services such as QA audit goes from $5,000 to $25,000. 

How can businesses know what type of software testing do they need?

Businesses can determine what type of testing solutions they need based on the potential impact of failures and the likelihood of defects. Namely, if they encounter:  

  • Core functionality issues: Use functional testing to verify features work as expected 
  • Unstable code or new features: Use unit testing for individual components and integration testing for modules working together 
  • Poor system stability after updates: Seek regression testing to make sure new changes didn't break existing features 
  • Performance and load issues: Use performance and load testing to evaluate speed and scalability 
  • Security issues: Security and penetration testing are commonly used across apps handling sensitive user data 
  • Hard-to-navigate user experience (UX): Pursue usability testing to determine how intuitive the application is for end users 
  • Low compatibility across devices: Compatibility testing can evaluate how good the app works on different browsers, devices, and OS versions 

There is also the option to choose between manual and automated testing.  

Is automated testing more expensive than manual testing?

As an investment, automated testing is pricier than manual testing but offers a lower cost-per-test over time as it can run the same scripts repeatedly, without human intervention. Conversely, manual testing entails lower upfront fee, but its cost grows linearly as the project grows, as every test cycle requires paid hours from QA testers.  

So, for short-term projects or ones with shifting requirements, manual testing is considered a more economical option, whereas for maintenance and regression cycles, automated testing grants better return on investment. 

The main distinction between these methodologies is that manual testing relies on human observation and interaction to identify defects, whereas automated testing uses software scripts to compare outcomes against predicted results.  

Manual testing is best suited for exploratory testing, usability assessments, ad-hoc bug hunting, and minor hotfix verifications where script development would be inefficient. Automated testing, on the other hand, is primarily used for regression testing to make sure the new code does not break existing features. 

How do businesses measure the effectiveness of software testing?

The effectiveness of the software testing is measured via: 

  • Code coverage: The percentage of the code that has been tested 
  • Defect density: The number of defects found per unit of code 
  • Test case effectiveness: The percentage of test cases that identify defects; helps prune redundant and ineffective tests 
  • Time to detect and fix defects: The time it takes to identify and fix software defects and software bugs 
  • Defect leakage: The number of bugs that "escaped" to production versus those caught during the testing phase Â