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jsDelivr

jsdelivr.com

jsDelivr is a free content delivery network for open-source projects. It serves files from npm and GitHub, so a site can load a library from a URL with no setup.[1]

jsDelivr is a free, open-source content delivery network (CDN) that specializes in serving JavaScript libraries, CSS frameworks, and other web assets. What sets jsDelivr apart is its ability to serve files directly from npm packages and GitHub repositories without any configuration, making it incredibly convenient for developers. It uses a multi-CDN infrastructure to ensure high availability and performance worldwide. jsDelivr supports version aliasing, allowing developers to always serve the latest version of a package, and it provides HTTPS support by default. With its user-friendly API and extensive documentation, jsDelivr has become a go-to solution for developers looking to optimize their web projects' performance and reduce hosting costs.

jsDelivr belongs toCDNcategory.

Price

Free[1]

Sources

npm packages and GitHub[1]

Network

Several CDN and DNS providers with failover[1]

Extras

Version ranges, on-demand minifying and a public API[1]

322websites

use it — 12.6% of the 2,560 websites we scanned in the last 12 months

#3of 29

tools in its category seen in our scans (we recognize 69)

160public pages

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

In short: a free way to load open-source libraries from npm or GitHub. Pin a version in the URL, because jsDelivr says not to use the latest-version form in production.[1]

13.6% of all websites we track run jsDelivr▲ 0.02 points since 20 Sep

Should you use jsDelivr?

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

jsDelivr fits if…

  • You want to load an npm or GitHub library from a URL with no setup[1]
  • You want version ranges and on-demand minified files[1]

Look elsewhere if…

  • You prefer a library CDN that is run on Cloudflare's network[2]cdnjs describes itself this way.
Do not omit the version in production URLs[1]

jsDelivr next to cdnjs

Statements come from each vendor's own home page; website counts are ours.

jsDelivrcdnjs
What the vendor says
PriceFree[1]Free[2]
Where files come fromnpm and GitHub[1]Open source librariesJavaScript, CSS and fonts[2]
What we see in our scans
Websites running it32212.6% of 2,560 scanned sites2489.7% of 2,560 scanned sites
Typical page load time4.7 s151 public sites4.6 s✓97 public sites
Typical page weight3.6 MB✓typical home page3.9 MBtypical home page
Security grade B or better29%✓12 of 42 graded sites score B or better21%7 of 34 graded sites score B or better

Each row shows what the vendor says about itself.

  • cdnjs: Another free CDN for open-source libraries, run on Cloudflare's network[2]

Choose jsDelivr if…

  • You want any npm package or GitHub file by URL[1]

Choose cdnjs if…

  • You want a curated library CDN on Cloudflare's network[2]

How jsDelivr sites protect themselves

Share of the 322 sites we scanned that run each protection

HSTS64% · 207 sites

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

reCAPTCHA24% · 78 sites

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

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

What sites use jsDelivr for

An estimate from UptimeCard's technology map of 130 public sites

Runs the whole site121 sites

2600hz.com · accredible.com · aplos.com

Runs the marketing site7 sites

aiia.eu · apphud.com · boltrics.com

Hosts help, docs or support content2 sites

aiven.io · balena.io

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.

At a glance

UptimeCard's own scans and tests of 2,560 websites · refreshed weekly

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

50PerformanceLowaverage site: 5090AccessibilityGoodaverage site: 8992Best practicesGoodaverage site: 9392SEOGoodaverage site: 92

Page load time

Loads about 10% slower than the average site

jsDelivr sites
4.7 s
All sites
4.3 s

Most jsDelivr sites load in 3.3–6.7 s. Home page weight: 3.6 MB vs 3.3 MB for all sites. 151 public sites measured.

Where are they hosted?

Mostly Cloudflare and Amazon Web Services

  • Cloudflare45%
  • Amazon Web Services18%
  • Google Cloud4%
  • Fastly4%
  • Other29%
United States 60%Canada 20%Netherlands 4%

Who uses it?

Software as a Service (SaaS) sites use jsDelivr 1.5× more than average

Technology and Software58%
Business Services12%
Software as a Service (SaaS)1.5× avg9%
Educational Resources6%

Share of 160 classified public sites. “× average” compares with all 961 public sites.

Browser-security check

29% of graded sites pass

12of 42 score B or better

Rates each site’s own security settings, not jsDelivr. 42 public sites graded so far.

How jsDelivr sites are built

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

Webflow6×jQuery CDN4×Slick4×Google Hosted Libraries3×cdnjs3×Reddit Ads3×Hotjar3×DoubleClick Floodlight2×HubSpot2×

Stacks we see most. Tools that tend to run together with jsDelivr on the same websites. The percentage is the share of all 322 jsDelivr sites that run the whole stack.

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

jsDelivr + Cloudflare + cdnjs + Bootstrap + jQuery CDN

4.7%15 of 322 sites
#2

jsDelivr + Cloudflare + Webflow + GSAP

5.3%17 of 322 sites
#3

jsDelivr + Cloudflare + YouTube

4.7%15 of 322 sites
#4

jsDelivr + Cloudflare + Cookiebot

4.3%14 of 322 sites
#5

jsDelivr + Webflow + Google Hosted Libraries + Unpkg

2.2%7 of 322 sites
#6

jsDelivr + Bootstrap + GSAP

2.5%8 of 322 sites
#7

jsDelivr + Marko + Algolia

2.5%8 of 322 sites
#8

jsDelivr + Bootstrap + Google Hosted Libraries

2.2%7 of 322 sites
#9

jsDelivr + Bootstrap + YouTube

2.2%7 of 322 sites

Usually installed alongside

The bigger the bubble, the more of the 322 jsDelivr sites also run the tool. Colour shows what the tool does. Hover or tap a bubble for details.

Google Tag Manager81%Google Analytics75%Facebook Pixel37%Linkedin Insight Tag34%DoubleClick Floodlight24%Microsoft Advertising20%Reddit Ads15%HubSpot21%Webflow21%OneTrust18%
Tag managerAnalyticsAdvertisingMarketingPage builderCookie consent

Similar tools in its category

CDN: 69 tools known, 29 seen in our scans

Amazon CloudFront335 sitesAlternativeAkamai205 sitesAlternativeAmazon S3184 sitesAlternativeGoogle Cloud CDN82 sitesAlternativeNetlify58 sitesAlternativeFastly57 sitesAlternativeImperva46 sitesAlternativeHostinger CDN22 sitesAlternativeCloudflare1,038 sitesUsed togethercdnjs248 sitesUsed togetherGoogle Hosted Libraries145 sitesUsed togetherUnpkg106 sitesUsed together

How websites combine jsDelivr with other tools

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

Overlaps with another 55Complements another tool 39Needs another tool 30Integrates with another 28Built on a platform 18

Websites using jsDelivr

322 websites use jsDelivr: 12.6% of the 2,560 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.

Questions about jsDelivr

Is jsDelivr free?
Yes. It describes itself as a free CDN for open-source projects.[1]
How do I load a package?
Use a URL with the package name, version and file path, for example for a package on npm.[1]
Should I leave out the version?
jsDelivr says leaving out the version returns the latest one and should not be used in production.[1]
How many websites use jsDelivr?
We found jsDelivr on 322 of the 2,560 websites we scanned in the last 12 months (12.6%). 160 of them have a public status page.
What is jsDelivr often used with?
Among the websites we scan, jsDelivr is often found alongside Google Tag Manager (81.1% of its sites), Google Analytics (75.2% of its sites), Cloudflare (66.1% of its sites).
What are the alternatives to jsDelivr?
Other CDNs we recognize include Cloudflare, Amazon CloudFront, cdnjs, Akamai.

Is your website built with jsDelivr?

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