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Technology · Web Development

Marko

markojs.com
Open source

Marko is an HTML-based language for building web apps. Just about any valid HTML is valid Marko, and it adds reactivity and components on top.[1][2]

Marko is an open-source UI library developed by eBay that reimagines HTML as a language for building dynamic and reactive user interfaces. It combines declarative UI components with a powerful templating syntax, allowing developers to create complex, high-performance web applications. Marko supports both server-side rendering and client-side interactivity, making it suitable for isomorphic applications. Its unique approach to UI development includes features like automatic UI updating, streaming rendering, and compiler optimizations, resulting in efficient and fast-rendering applications.

Marko belongs toUI frameworksWeb frameworkscategories.

What it is

A declarative, HTML-based language[1]

Rendering

Streaming, resumable, with an optimizing compiler[2]

Types

Built-in TypeScript support[2]

License

Free and open source under the MIT license[3]

149websites

use it — 5.8% of the 2,555 websites we scanned in the last 12 months

#4of 57

tools in its category seen in our scans (we recognize 200)

115public pages

on UptimeCard — open any of them to see how that site is doing

In short: a free, HTML-first framework that streams pages as content is ready. Older apps move to the new component API at their own pace.[2][4]

2.24% of all websites we track run Marko▲ 0.02 points since 20 Sep

Should you use Marko?

The 10-second version, from the vendor’s own pages and what we see in our scans

Marko fits if…

  • You know HTML, CSS and JavaScript and want a syntax close to them[2]
  • You want pages to start rendering before all data requests finish[2]

Look elsewhere if…

  • You want a framework with a template syntax that extends standard HTML inside single-file components[5]Vue describes itself this way.
The newest major version brings a new component API; apps on the older one keep working until you move them[4]

Marko next to its closest alternatives

Other ways to build a web interface. Statements come from each project's own page; website counts and speed are ours.

MarkoVue.jsSvelte
What each one says it is
What it isAn HTML-based languagefor building web apps[1]A frameworkfor web user interfaces[5]A UI frameworkbuilt around a compiler[6]
What we see in our scans
Websites running it1495.8% of 2,555 scanned sites1445.6% of 2,555 scanned sites240.9% of 2,555 scanned sites
Typical page load time5.1 s107 public sites4.6 s✓24 public sites—
Typical page weight3.6 MBtypical home page2.7 MB✓typical home page—

Scan rows count public pages only; a tool needs at least 5 measured sites to appear.

  • Vue.js: A framework for building web user interfaces[5]
  • Svelte: A UI framework that uses a compiler[6]

Choose Marko if…

  • You want content streamed to visitors as soon as it is ready[2]

Choose Vue.js if…

  • You want a template syntax that extends standard HTML and a framework you can adopt step by step[5]

Choose Svelte if…

  • You want a compiler so components do little work in the browser[6]

Support and help for Marko

How the vendor says you can reach it, and the public help community

Stack Overflow

64 questions[9][10]

73% have an upvoted answer. [marko] questions

Marko versions

The newest release, the series that still gets fixes, and what changed

Latest release

6.4.6[7]

Maintained series

6

The newest major version is tagged latest on npm and is the default for new installs[4]

What changed in 6

  • Marko 6 became the default on npm and moved new projects to the Tags API[4]
  • Existing class API apps keep working and can move over when ready[4]

What changed in 5

  • Marko 5 moved the compiler onto Babel and focused on developer experience[8]

What Marko sites add on top

How many of the 149 Marko sites we scanned also run each tool, grouped by what the tool does

Tag manager

Google Tag Manager
63%94 sites

Analytics

Google Analytics
62%92 sites
Linkedin Insight Tag
36%54 sites
Piwik PRO Core
30%45 sites

Marketing

Qualified
39%58 sites
Marketo
19%28 sites
HubSpot
13%20 sites

Cookie consent

OneTrust
27%40 sites

The full bar means every Marko site. A site can run several tools for one job, so the shares of tools in one group can add up to more than 100%.

How Marko sites protect themselves

Share of the 149 sites we scanned that run each protection

HSTS83% · 123 sites

HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS

reCAPTCHA34% · 50 sites

reCAPTCHA is a free service from Google that helps protect websites from spam and abuse

Cloudflare Bot Management15% · 22 sites

Cloudflare bot management solution identifies and mitigates automated traffic to protect websites from bad bots

Protections add up, they do not replace each other: a site can run all of them.

What sites use Marko for

An estimate from UptimeCard's technology map of 51 public sites

Runs the whole site30 sites

abbyy.com · appspace.com · autotrader.ca

Runs the marketing site16 sites

aiia.eu · bird.com · braze.com

Hosts help, docs or support content3 sites

hiverhq.com · northflank.com · optimizely.com

Runs a shop or catalog2 sites

alation.com · goshippo.com

Rough guide, not a measurement: each description is written automatically from the site’s technology stack and the site has not confirmed it. A site is counted once, in the first group its description fits (shop, help and docs, blog, marketing site; otherwise the whole site). Descriptions that only guess (“likely”, “may”) are left out.

The speed trap: what fast Marko sites do differently

107 public Marko sites we measured, split by how fast their page loads

Fastest quarter

2.8 stypical page load time

2.9 MB page · 116 requests

Slowest quarter

10.0 stypical page load time

4.4 MB page · 215 requests

What differs between the two groups

Extras on the site
Cloudflare35%62%
Next.js46%19%
jsDelivr8%27%
React50%31%
Piwik PRO Core27%42%
Google Tag Manager77%65%
Read this as a pattern, not a cause. The sites in the slower group more often add the extras above. Marko itself is not what separates the two groups.

At a glance

UptimeCard's own scans and tests of 2,555 websites · refreshed weekly

How Marko sites scoreout of 100 · hover or tap a score for details

41PerformancePooraverage site: 5089AccessibilityGoodaverage site: 8979Best practicesFairaverage site: 9392SEOGoodaverage site: 92

Page load time

Loads about 20% slower than the average site

Marko sites
5.1 s
All sites
4.3 s

Most Marko sites load in 3.5–7.6 s. Home page weight: 3.6 MB vs 3.3 MB for all sites. 107 public sites measured.

Where are they hosted?

Mostly Amazon Web Services and Cloudflare

  • Amazon Web Services39%
  • Cloudflare25%
  • Fastly10%
  • Google Cloud4%
  • Other21%
United States 60%Canada 28%SE 2%

Who uses it?

Technology and Software is the biggest group

Technology and Software57%
Business Services15%
Educational Resources4%
Software as a Service (SaaS)4%

Share of 115 classified public sites. “× average” compares with all 961 public sites.

Browser-security check

40% of graded sites pass

14of 35 score B or better

Rates each site’s own security settings, not Marko. 35 public sites graded so far.

How Marko sites are built

Closest partners. The number says how many times more often the tool runs on Marko sites than on an average website. Hover a partner for its share of sites.

Qualified13×PyScript7×Marketo6×Python5×Algolia5×Piwik PRO Core4×DoubleClick Floodlight4×Reddit Ads3×Tailwind CSS3×

Stacks we see most. Tools that tend to run together with Marko on the same websites. The percentage is the share of all 149 Marko sites that run the whole stack.

15 stacks · swipe, drag or use the arrows
#1

Marko + React + OneTrust + Next.js + Tailwind CSS

5.4%8 of 149 sites
#2

Marko + OneTrust + Amazon S3

6%9 of 149 sites
#3

Marko + jsDelivr + Algolia

5.4%8 of 149 sites
#4

Marko + OneTrust + Vue.js

4.7%7 of 149 sites
#5

Marko + OneTrust + jsDelivr

4%6 of 149 sites
#6

Marko + jsDelivr + Amazon S3 + AWS Certificate Manager

2.7%4 of 149 sites
#7

Marko + React + Sentry + Turbopack

2.7%4 of 149 sites
#8

Marko + Varnish + Drupal + Fastly

2.7%4 of 149 sites
#9

Marko + jsDelivr + Sentry

3.4%5 of 149 sites
#10

Marko + Tailwind CSS + Amazon S3

3.4%5 of 149 sites
#11

Marko + Tailwind CSS + AWS Certificate Manager

3.4%5 of 149 sites
#12

Marko + Amazon S3 + Algolia

3.4%5 of 149 sites
#13

Marko + AWS Certificate Manager + Algolia

2.7%4 of 149 sites
#14

Marko + Tailwind CSS + Contentful

2.7%4 of 149 sites
#15

Marko + Algolia + Netlify

2.7%4 of 149 sites

Similar tools in its category

UI frameworks: 200 tools known, 57 seen in our scans

Bootstrap314 sitesAlternativeMicrosoft ASP.NET79 sitesAlternativeNuxt.js47 sitesAlternativeExpress36 sitesAlternativeAnimate.css33 sitesAlternativeZURB Foundation26 sitesAlternativeRuby on Rails25 sitesAlternativeMaterial UI24 sitesAlternativeNext.js375 sitesUsed togetherTailwind CSS208 sitesUsed togetherHeroUI60 sitesUsed togetherRadix UI41 sitesUsed together

How websites combine Marko with other tools

Relationships found on the websites that use it, from the same map status pages show.

Built on a platform 47Needs another tool 36Overlaps with another 26Integrates with another 24Complements another tool 16

Websites using Marko

149 websites use Marko: 5.8% of the 2,555 websites we scanned in the last 12 months. A selection is shown below.

Scores are out of 100: P Performance · A Accessibility · B Best practices · S SEO. Green 80+, yellow 65–79, orange 50–64, red below 50. The dot shows whether our last scan found the site failing (red) or not (green); Red, amber or blue: an active incident on the site's status page (outage, degraded, maintenance) or a failing scan; amber also means a certificate ending within 30 days. Hover the dot for details.

Who is behind Marko

From its own pages and public records, with sources

Marko

since 2012[8]

Its story

  1. 2012

    eBay began developing Marko to move from a Java stack to a Node stack. It aimed to keep server-side rendering and progressive, asynchronous HTML that the Java stack had provided.[8][11]

  2. 2014

    The first stable release came in May. Marko was written to address limits of the Dust templating library and to tie client-side code to templates as reusable widgets.[11]

  3. 2017

    The open source project moved to be hosted by the OpenJS Foundation alongside other well-known JavaScript projects. eBay still actively maintained it, so governance became vendor-neutral.[11][8]

  4. 2021

    Marko 5 was the first major release since 2017. Its compiler moved onto Babel, so current JavaScript syntax and the wider tooling ecosystem worked with Marko templates.[8]

  5. 2026

    Marko 6 became the default on npm in June. New projects start on the Tags API runtime, while existing Marko 5 applications keep working and can move over later.[4]

Questions about Marko

What is Marko?
An HTML-based language for building web apps, where almost any valid HTML is also valid Marko.[1][2]
Is Marko free?
Yes. It is open source under the MIT license.[3]
Does Marko support TypeScript?
Yes. TypeScript support is built in, with type inference across templates and components.[2]
Which version do new projects get?
The newest major version. It is tagged latest on npm, so a plain install brings in the Tags API.[4]
How many websites use Marko?
We found Marko on 149 of the 2,555 websites we scanned in the last 12 months (5.8%). 115 of them have a public status page.
What is Marko often used with?
Among the websites we scan, Marko is often found alongside Amazon Web Services (43.6% of its sites), PHP (43% of its sites), Qualified (38.9% of its sites).
What are the alternatives to Marko?
Other ui frameworks tools we recognize include Next.js, Bootstrap, Tailwind CSS, Microsoft ASP.NET.

Is your website built with Marko?

UptimeCard checks it around the clock, tells you the minute it stops answering, and gives your visitors a status page.

Monitor my site freeCreate a status page