Top 60 JavaScript Development Companies in Seattle

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Top 60 JavaScript Development Companies in Seattle

March 2023

Looking for a top JavaScript developer in Seattle?

If you're hiring a JavaScript developer to help you build or update a website that's responsive and interactive, consider the pros and cons of JavaScript as a programming language. Advantages include its speed because it's executed on the client-side; reduction in server load; and diverse functionality. 

Jump to Most Reviewed Companies

List of the Best Seattle JavaScript Developers

  • 1
    • $1,000+
    • 50 - 249 employees
    • Seattle, WA

    Headquartered outside Los Angeles in Culver City, CA, Coalition Technologies specializes in SEO and PPC but also offers web design, e-commerce development, and WordPress development. With additional offices in Austin, TX and Seattle, WA, Coalition Technologies has grown to a team of 100+ since its founding in 2009.

    Clients

    • PayPal
    • Natori
    • Harvard
    • Whataburger

    Industries

    Notable Project

    Coalition Technologies provides ongoing SEO services for a pet products company. The team was hired to diagnose SEO issues and implement a plan to fix issues.

    "I feel like I am in good hands now. So far everything is already improving."

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  • 2
    • $25,000+
    • 2 - 9 employees
    • Seattle, WA

    Lunarbyte.io is a development agency based in Seattle. Since 2019, the 3-person team has built websites, custom software, and mobile apps for predominantly small businesses.  

    Clients

    • DDM Imports
    • Clean the Scene
    • Preflight Mitigator
    • Dollar Flight Club

    Industries

    Notable Project

    Lunarbyte.io provides development support for a flight deal platform. They’ve architected solutions for its payment processing, transactional issues, and mailing systems. The partnership is ongoing.

    "Working with Lunarbyte.io is the easiest part of our day."

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  • 3
    • Scheduling

      5.0
    • Quality

      5.0
    • Cost

      5.0
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $25,000+
    • 10 - 49 employees
    • Seattle, WA

    Zazz is a Seattle-based mobile app development company founded in 2011. They have an additional office in San Francisco. Their team of approximately 50 employees serves clients of all sizes and industries. In addition to app development, they also specialize in enterprise app modernization and UX/UI design.

    Clients

    • Inclose
    • Ideal Smart
    • Sparehandz

    Industries

    Notable Project

    Zazz has designed a mobile application for an employee wellness and fitness company. They’ve used Figma for the design, and they’re currently working on development using React Native, MongoDB, and Node.js.

    “We like that Zazz cares about the details. They’re great at explaining everything they’re doing.”

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  • 4
    • Scheduling

      4.9
    • Quality

      5.0
    • Cost

      5.0
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $25,000+
    • 50 - 249 employees
    • Bellevue, WA

    MSOFT (formerly MediaSoft.team) is a Washington State, software development firm with an office in Bellevue, Seattle area. Founded in 2014, MSOFT (formerly MediaSoft.team) team of over 270 employees specializes in custom software, website, and mobile app development for enterprise clients. MSOFT (formerly MediaSoft.team) has partners in a variety of industries including Retail, GameDev, and FinTech.

    Clients

    • Zdravcity
    • CarPrice
    • Moio Delo
    • Svaznoy Travel

    Industries

    Notable Project

    MSOFT (formerly MediaSoft.team) developed a mobile app, as well as the technology to connect a vast database of content to the app. They also implemented the graphic design.

    "During the development process, they came up with a number of new ideas that greatly improved the app."

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  • 5
    • $10,000+
    • 2 - 9 employees
    • Seattle, WA

    Black Antelope is a digital creative industry headquartered in Seattle. It was founded in 2009 and has expanded to additional locations in Sacremento, Calif. and London. Black Antelope has about 3 employees that serve a range of enterprise and small- to mid-sized businesses. Services include custom software development, web development, and web design. 

    Clients

    • UC Berkeley (Berkeley, CA)
    • UCSF (San Francisco, CA)
    • Monterey Bay Aquarium (Monterey, CA)
    • Fujitsu Laboratories Of America (Sunnyvale, CA)

    Industries

    Notable Project

    A college university hired Black Antelope to migrate their website into a new platform and enhance their backend framework. The goal is to design and develop a new website for a specific school program.

    "The design aspect is fast, efficient, and top-notch."

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  • 7
    • Scheduling

      5.0
    • Quality

      5.0
    • Cost

      5.0
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $1,000+
    • 2 - 9 employees
    • Seattle, WA

    A digital marketer based in San Francisco, Randy McCabe offers SEO, PPC, and digital strategy services. They were founded in 2018.

    Clients

    • Morgan Stanley
    • Huawei
    • NameSilo
    • RE/MAX

    Industries

    Notable Project

    Exo Agency has developed the website of a foundation repair company. They've also helped the client rank on the first page of Google through their efforts. The team has also managed the client's PPC campaigns.

    "Randy is extremely specialized in his field."

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  • 8
    • $1,000+
    • 50 - 249 employees
    • Bellevue, WA

    Founded in 2014, Golden Eagle IT Technologies Pvt. Ltd. Is a SEO services firm. The midsize Indore, India-based team provides search engine optimization, custom software development, web design, ux/ui design, and more.

    Industries

    Notable Project

    Golden Eagle It technologies provides staff augmentation services for an IT services firm. The vendor has deployed several Ruby on Rails developers to help the client complete a specific project.

    "We’re impressed with their ability to communicate well and deliver the project on time."

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  • 9
    • $25,000+
    • 10 - 49 employees
    • Seattle, WA

    Culture Foundry is a web agency founded in Seattle in 2010 with more than 10 employees. They specialize in digital strategy, web design, and web development solutions for small and mid-market firms in the fields of arts, IT, and financial services.

    Clients

    • 24 Hour Fitness
    • Audinate
    • Ballet Austin
    • Belmont Stakes / NYRA

    Industries

    Notable Project

    Culture Foundry was hired by a racing association to update their site's structure, design, and backend setup. The team now conducts regular audits to help improve customer experience on the site's front end.

    "Culture Foundry's team members are committed to working together to help achieve our business goals."

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  • 10
    • Scheduling

      5.0
    • Quality

      5.0
    • Cost

      4.9
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $5,000+
    • 10 - 49 employees
    • Seattle, WA

    Slashdev is a small software development company. The Winter Park, Florida-based company was established in 2021. Their services include custom software development, web development, mobile app development, wearable app development, and more.

    Industries

    Notable Project

    Slashdev helped develop an iOS app for a large Swedish bank by recruiting and assigning a software engineer to build, maintain, and improve the mobile platform.

    "The best recruiter we've worked with."

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  • 11
    • Scheduling

      4.9
    • Quality

      5.0
    • Cost

      4.9
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $25,000+
    • 10 - 49 employees
    • Seattle, WA

    Founded in 2010 in Seattle, Billberry is a software development studio creating custom software, web apps, and digital products in partnership with some of the world's biggest brands. They have a veteran team of fewer than 50 strategists, designers, and developers who work in partnership with clients to help them grow, innovate, and move their businesses forward. Clients include businesses of all sizes in various industries, including business services, consumer products and services, and financial services.

    Clients

    • Days for Girls
    • Snohomish County Public Utilities
    • Impinj
    • The Live You Can Save

    Industries

    Notable Project

    A fundraising company was looking to improve their online presence, so they engaged with Bilberrry to provide them with WordPress web development, design, branding, and ongoing maintenance and hosting.

    "I highly recommend employing their services because Bilberrry is relatable and easy to work with."

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  • 12
    • $10,000+
    • 10 - 49 employees
    • Medina, WA

    A full-service digital design and development agency, Flower Press Creative Studio takes on mobile app, web, and custom software development projects. Founded in 2001, the small team of 6 is headquartered in Seattle and also has experience in UI/UX design.

    Clients

    • Insurance Lounge
    • Brown Bear Car Wash
    • Geek Girl Careers
    • World Perspectives

    Industries

    Notable Project

    A medical device firm had an outdated site, and they hired Flower Press Creative Studio, LLC to create their WordPress site. The site featured the company's description, contact form, and downloadable brochure.

    "Their efficiency was their strong point."

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  • 13
    • $5,000+
    • 10 - 49 employees
    • Seattle, WA

    Codersh Web Services is a web agency based in Ahmedabad, India, and founded in 201. With no more than 10 experts, they specialize in web design, web development, and mobile app development services for small firms in the industries of business and IT services, among others.

    Clients

    • Reinventu Pro
    • Redesign Hub
    • Vidste
    • Bahia Days

    Industries

    Notable Project

    Codersh Web Services is helping build the website of a religious matchmaking platform. This also involves implementing various features and applying necessary improvements in terms of design.

    "Their work is very good, and I am happy with it."

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  • 14
    • $1,000+
    • 10 - 49 employees
    • Seattle, WA

    Seattle New Media is a website development agency based in Seattle. The agency, founded in 2006, has a team of less than ten that provides, among others, video production, web development, and mobile app development services to various companies and clients. 

    Clients

    • Dr. Tracy
    • Clearview.ai

    Industries

    Notable Project

    Seattle New Media designed and developed Webflow website with multiple pages for a mobile marketplace. They were also tasked with transferring the site to a custom domain.

    "We were impressed with the quality of work they provided at an affordable price."

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  • 15
    • $1,000+
    • 2 - 9 employees
    • Seattle, WA

    Visualwebz is a digital design and marketing agency located in Renton, Wash., with under 10 employees. Founded in 2008, the company mainly provides web design and development, e-commerce development, SEO services, and content marketing using a variety of programs and systems.

    Clients

    • TimeXtender
    • Mitsubishi
    • Fuso
    • PGTAA

    Industries

    Notable Project

    VisualWebz, LLC is developing multiple sites using WordPress. They oversee creative development, system management, software updates, and web security. 

    "Their team makes things simple, easy, and are a pleasure to work with."

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  • 16
    • $5,000+
    • 10 - 49 employees
    • Seattle, WA

    Hero Creative is a Seattle-based media production company founded in 2012. Their team of around 10 employees provides marketing strategy, branding, advertising and web design. They primarily serve enterprise clients in the advertising, hospitality and nonprofit industries.

    Clients

    • Make-A-Wish Foundation
    • University of Washington
    • Leukemia and Lymphoma Society
    • Northwest Motorsport

    Industries

    Notable Project

    Hero Creative offers full-service creative for a property management firm’s clients. Their support spans video production, website development, creative strategy, and branding.

    “They’re a fun group to work with, and their deliverables are top-notch.”

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  • 17
    • Scheduling

      4.9
    • Quality

      5.0
    • Cost

      4.8
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $5,000+
    • 10 - 49 employees
    • Seattle, WA

    Conflare is a web development and design firm in Seattle. It was founded in 2004 and currently has 4 employees. Conflare provides web design and development, branding, digital strategy, and video production services mainly to small business clients.

    Clients

    • Artisan Electric
    • PhotoTC
    • AME Commerce
    • Foundry Law

    Industries

    Notable Project

    Conflare gave branding counsel and built a jewelry retail website from scratch. The team custom-coded a complex design-your-own-ring feature and now provides ongoing site updates and product adds.

    "Everyone is impressed with the site."

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  • 18
    • Scheduling

      4.0
    • Quality

      4.0
    • Cost

      3.0
    • NPS

      4.0
    Read Full Reviews on Clutch Visit Site
    • $5,000+
    • 50 - 249 employees
    • Seattle, WA

    Forum One is a full-service digital design firm that was founded in 1997. The company has more than 100 employees in Alexandria, Va., Washington, D.C., and Seattle. Forum One offers web design, UX/UI design, web development, branding, and other digital services for mainly nonprofits and government agencies.

    Clients

    • Smithsonian Institution (National Museum of African American History & Culture
    • National Museum of Natural History and the National Zoo)
    • Global Impact
    • Patient Centered Outcomes Research Institute (PCORI)

    Industries

    Notable Project

    In order to prepare a large museum for its opening, Forum One built a Drupal 7 site within institutional infrastructure, with strong SEO and consistent UX across a variety of devices.

    “They brought a lot of experience from different clients across a variety of sectors, and we’ve benefited from that.”

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  • 19
    • Scheduling

      4.8
    • Quality

      4.8
    • Cost

      4.3
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $100,000+
    • 250 - 999 employees
    • Seattle, WA

    Founded in 2014, PYCOGroup is a development firm. Their team of around 370 employees is based in Brussels, with an additional office around the globe. They focus on custom software, web, and mobile app development.

    Clients

    • Microsoft
    • American Express
    • Volkswagen
    • Coach

    Industries

    Notable Project

    PYCOGroup designed and developed a government-funded mobile app to promote travel. While the internal team focused on the database and API, PYCOGroup focused on everything else, including delivery.

    "The workflow was very fluid, efficient, and professional on PYCOGroup's side."

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  • 20
    • Scheduling

      5.0
    • Quality

      5.0
    • Cost

      4.5
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $25,000+
    • 50 - 249 employees
    • Bellevue, WA

    Redtech is a custom software development firm. They are located in Bellevue, Washington and have a midsize team. Their services include custom software development, non-voice bpo/back office services, digital strategy, web development, and more. The agency was established in 1995.

    Notable Project

    Redtech provided BI and analytics for a software company. They redesigned a learning catalog and supported in understanding its current status.

    "Their subject matter expertise and professionalism were impressive."

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  • 21
    • $5,000+
    • 10 - 49 employees
    • Bellevue, WA

    Truu Digital, a website development company, was established in 2012. The small Bellevue, Washington-based team provides web development, conversion optimization, CRM consulting and SI, digital strategy, and more.

    Industries

    Notable Project

    Truu Digital developed a website for a chiropractor practice. The team built and designed a new website with a more modern image.

    "They are up to date with technology, communicate well, and listen to your needs."

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  • 22
    • $10,000+
    • 10 - 49 employees
    • Seattle, WA

    Helpful Human is a development agency based in Seattle. Since 2013, their team of 15 has been specializing in web design and development, mobile app development, and UX/UI design. They work primarily with small businesses in the information services and business services industries.

    Clients

    • Rudy's
    • naturewise
    • Elm Coffee Roasters
    • Holland America Line

    Industries

    Notable Project

    Helpful Human provides custom software development services for an aerospace consulting services company. They are helping the client develop an advanced production scheduling software.

    "They are highly dynamic and have a great level of technical knowledge to support our requirements."

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  • 23
    • $25,000+
    • 2 - 9 employees
    • Seattle, WA

    Northwest Independent Ruby Development is a digital agency based in Seattle. Since 2011, the small team of four has specialized in providing web and custom software development. 

    Clients

    • University of Washington
    • Avvo
    • Whitepages
    • Behavioral Tech

    Notable Project

    NIRD provided resources to help bring the Linehan Suicide Safety Net to market. They made the online software HIPAA compliant and reworked the backend to make it more stable.

    "NIRD helped us get our program in a place where it was healthy and functioning the way it should be."

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  • 24
    • Scheduling

      5.0
    • Quality

      5.0
    • Cost

      4.5
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $25,000+
    • 2 - 9 employees
    • Seattle, WA

    Gigantic is a web design agency founded in 2020. The agency specializes in web design, ux/ui design, web development, branding, and more and has a small team.

    Notable Project

    An advertising agency was looking to rebrand their image and online presence, so they engaged with Gigantic to provide them with web development, SEO management, and marketing campaigns and strategies.

    "They delivered above and beyond what we were expecting."

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  • 25
    • Scheduling

      4.9
    • Quality

      4.9
    • Cost

      5.0
    • NPS

      5.0
    Read Full Reviews on Clutch Visit Site
    • $1,000+
    • 10 - 49 employees
    • Redmond, WA

    Designify is a web agency based in Redmond, Wash., and founded in 2017. With no more than 50 members, they specialize in web development, web design, and SEO solutions for small and mid-market businesses in the fields of business services, consumer products, and e-commerce.

    Clients

    • Startline
    • Chipmonk Consulting
    • Center Source Inc

    Industries

    Notable Project

    Designify recreated a legacy website with the aim of improving its functionality and visual appeal. This involved creating new features for the platform.

    "The Designify team took my poorly designed website and turn it into a modern and attractive expression of my company."

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  • 26
    • $10,000+
    • 50 - 249 employees
    • Bellevue, WA

    Virtuosity Consulting, a custom software development firm, was launched in 2008. They are located in Bellevue, Washington and Navi Mumbai, India and have a midsize team. Their services include custom software development, IT managed services, enterprise app modernization, web development, and more.

    Industries

    Notable Project

    A software company hired Virtuosity Consulting for staff augmentation. The team supplied qualified process-driven and self-motivated managers for early planning, daily execution, monthly releases, and more. 

    "The agency and the candidates they supplied really took ownership of the project."

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  • 27
    • $1,000+
    • 10 - 49 employees
    • Seattle, WA

    Steelsmith Haus LLC is an internet marketing agency in Seattle. Founded in 2010, Steelsmith Haus has about 8 employees that work with a range of clients. Services include SEO, content marketing, web design, and email marketing services.

    Clients

    • StacheClip
    • Starving Students
    • UC Berkeley
    • StemGenex

    Industries

    Notable Project

    Steelsmith Haus built a new website and subsequently created a marketing strategy. Post-launch, they’ve provided SEO and PPC.

    "The team does a phenomenal job with web development and marketing."

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  • 28
    • Undisclosed
    • 2 - 9 employees
    • Seattle, WA
    Perception Builder is a small conversion optimization company in Seattle, Washington. Established in 2011, the team focuses on conversion optimization, search engine optimization, ux/ui design, and web development.

    Industries

    Notable Project

    Perception Builder has been hired by a power sweeping company to update their website, develop new marketing strategies, provide SEO services, and create content for the website's overall improvement.

    "We were impressed by their technical capabilities."

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  • 29
    • $5,000+
    • 50 - 249 employees
    • Bellevue, WA
    Tech Pathway is a web development firm. Established in 2017, the midsize agency is located in Jaipur, India and Bellevue, Washington. Their team focuses on web development, mobile app development, and e-commerce development.

    Industries

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  • 30
    • $100,000+
    • 50 - 249 employees
    • Seattle, WA
    Carbon Five is a software development firm. Established in 2000, the midsize company is located in San Francisco, California; Santa Monica, California; Chattanooga, Tennessee and New York, New York. Their services include custom software development, mobile app development, web development, web design, and more.

    Industries

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