--- title: "cdnjs Explained: How the Public JavaScript CDN Works" description: What cdnjs is, how libraries get added, how it is cached and served, and when to use cdnjs versus bundling or other public CDNs. image: https://blog.blazingcdn.com/hubfs/Gemini-Blog/image-Oct-18-2026-07-00-43-6295-AM.jpeg --- [![BlazingCDN](https://blog.blazingcdn.com/hubfs/Logo/blog-logo-w.png)](https://blog.blazingcdn.com?hsLang=en-us) [๐Ÿ“˜Learn โ–พ](https://blog.blazingcdn.com/cdn-learn?hsLang=en-us) [CDN Fundamentals](https://blog.blazingcdn.com/cdn-fundamentals?hsLang=en-us) [By Content Type](https://blog.blazingcdn.com/by-content-type?hsLang=en-us) [Advanced Concepts](https://blog.blazingcdn.com/advanced-concepts?hsLang=en-us) [Glossary](https://blog.blazingcdn.com/glossary?hsLang=en-us) [โšก Web Performance](https://blog.blazingcdn.com/web-performance?hsLang=en-us) [๐ŸŽฌVideo & Streaming โ–พ](https://blog.blazingcdn.com/video-streaming-cdn?hsLang=en-us) [๐Ÿ”ด Live Streaming](https://blog.blazingcdn.com/live-streaming?hsLang=en-us) [๐Ÿ“บ VOD & OTT](https://blog.blazingcdn.com/vod-ott?hsLang=en-us) [๐Ÿ’ฐ Bandwidth & Costs](https://blog.blazingcdn.com/bandwidth-costs?hsLang=en-us) [๐Ÿญ Other Industries โ–พ](https://blog.blazingcdn.com/cdn-industry-insights?hsLang=en-us) [๐Ÿ“บ Media & Broadcasting](https://blog.blazingcdn.com/media-broadcasting?hsLang=en-us) [๐Ÿ’พ Software & SaaS](https://blog.blazingcdn.com/software-saas?hsLang=en-us) [๐Ÿ—๏ธ DevOps & Cloud Infra](https://blog.blazingcdn.com/devops-cloud-infra?hsLang=en-us) [๐Ÿ“š AdTech & Advertising](https://blog.blazingcdn.com/adtech-advertising?hsLang=en-us) [๐ŸŽฎ Gaming & Esports](https://blog.blazingcdn.com/gaming-esports?hsLang=en-us) [๐Ÿ“ฑ Mobile Apps & Developers](https://blog.blazingcdn.com/mobile-apps-developers?hsLang=en-us) [๐Ÿค– AI & Machine Learning](https://blog.blazingcdn.com/ai-machine-learning?hsLang=en-us) [๐Ÿ›๏ธ Enterprise & Corporate](https://blog.blazingcdn.com/enterprise-corporate?hsLang=en-us) [๐Ÿ“š E-Learning & EdTech](https://blog.blazingcdn.com/e-learning-edtech?hsLang=en-us) [๐ŸŸ๏ธ Sports & Live Events](https://blog.blazingcdn.com/sports-live-events?hsLang=en-us) [๐Ÿ’ฐ Pricing & Costs โ–พ](https://blog.blazingcdn.com/cdn-pricing-and-cdn-costs?hsLang=en-us) [Provider Pricing](https://blog.blazingcdn.com/provider-pricing?hsLang=en-us) [Cost Optimization](https://blog.blazingcdn.com/cost-optimization?hsLang=en-us) [Decision Support](https://blog.blazingcdn.com/decision-support?hsLang=en-us) [โšกCompare โ–พ](https://blog.blazingcdn.com/cdn-comparison?hsLang=en-us) [Provider Comparisons](https://blog.blazingcdn.com/provider-comparisons?hsLang=en-us) [Strategy Comparisons](https://blog.blazingcdn.com/strategy-comparisons?hsLang=en-us) [Ratings & Benchmarks](https://blog.blazingcdn.com/cdn-ratings-and-benchmarks?hsLang=en-us) [๐Ÿ“Š Benchmarks](https://blog.blazingcdn.com/cdn-ratings-and-benchmarks?hsLang=en-us) [๐Ÿ”’ Security โ–พ](https://blog.blazingcdn.com/cdn-security?hsLang=en-us) [Attack Protection](https://blog.blazingcdn.com/attack-protection?hsLang=en-us) [Encryption & Access](https://blog.blazingcdn.com/encryption-access?hsLang=en-us) [Video & DRM Security](https://blog.blazingcdn.com/video-drm-security?hsLang=en-us) [๐Ÿ“ Case Studies](https://blog.blazingcdn.com/case-studies?hsLang=en-us) [๐Ÿ”Œ Integrations](https://blog.blazingcdn.com/integrations?hsLang=en-us) [๐Ÿ› ๏ธ Tools](https://blog.blazingcdn.com/cdn-tools?hsLang=en-us) [Get Started](https://blazingcdn.com/sign-up-contact-form/) [Learn](https://blog.blazingcdn.com/en-us/tag/learn) [Learn - CDN Fundamentals](https://blog.blazingcdn.com/en-us/tag/learn-cdn-fundamentals) # cdnjs Explained: How the Public JavaScript CDN Works Vadym Borovskyi Oct 18, 2026, 9:03:08โ€ฏAM ![](https://blog.blazingcdn.com/hubfs/Gemini-Blog/image-Oct-18-2026-07-00-43-6295-AM.jpeg) cdnjs is an open-source public JavaScript CDN that serves more than 4,000 libraries (2025 index size) from Cloudflare's edge network. Every file sits at an exact, versioned URL, is cached for roughly a year, and ships with a precomputed Subresource Integrity (SRI) hash. Libraries enter through a reviewed package definition on GitHub, and an automated bot then picks up each new npm or Git release. This guide covers that pipeline, how files are cached and served, how to pin versions and apply SRI correctly, what breaks in production, and a decision matrix for cdnjs versus jsDelivr, unpkg and self-hosting. Browsers now partition their HTTP caches by top-level site: Safari did so first, then Chrome 86 in 2020 and Firefox 85 in 2021. A copy of jQuery cached from cdnjs on one site is therefore never reused on another, and the old shared-cache argument for public CDNs no longer holds. What cdnjs still offers is zero build tooling, a large global edge and an immutable, hash-verifiable URL. ## **How cdnjs Works: From Package Definition to Edge** cdnjs is not a mirror of npm. It serves a curated index, and each library in it has a small JSON package definition. That definition names the upstream source (an npm package or a Git repository) and a file map: which directories and glob patterns from each release get published. Everything downstream of that definition is automated. ### How libraries get added to cdnjs To add a library, a contributor opens a pull request against the cdnjs packages repository with a new package definition. CI validates the definition and a maintainer reviews it. The contribution guidelines ask for a minimum popularity signal, historically around 200 GitHub stars or 800 monthly npm downloads, so cdnjs does not become a dumping ground. Once the definition is merged, the auto-update bot polls the upstream source for new versions. For each version it fetches the matching files, minifies JavaScript and CSS that arrive unminified, generates SRI hashes, precompresses the files and pushes them to storage behind Cloudflare. ### How fast new releases appear Expect a new upstream release to appear on cdnjs within minutes to a few hours (our estimate, based on the polling design). Releases with non-standard version tags, renamed build directories or files that no longer match the file map can stall until someone updates the package definition. If a security fix needs to ship within the hour, do not make cdnjs propagation part of your critical path. ### How cdnjs files are cached and served A cdnjs URL has four parts: the cdnjs.cloudflare.com hostname, the ajax/libs prefix, the library name and exact version, then the file path. Because a published version never changes, responses carry a long public Cache-Control lifetime, around 30.7 million seconds, or roughly 355 days, marked immutable in observed response headers. They also send a wildcard Access-Control-Allow-Origin header, which SRI needs, and are served with Brotli or gzip over HTTP/2 and HTTP/3 from Cloudflare's anycast network. ## **What a JavaScript CDN Is For in 2026, and Where cdnjs Fits** A public JavaScript CDN hosts third-party open-source libraries so a page can reference them by URL instead of bundling them. Today that suits pages with no build step: CMS themes, server-rendered admin tools, documentation sites, prototypes and legacy applications. Teams already running Vite, webpack or esbuild get tree-shaking, a single first-party origin and full control by bundling instead. Within that category, cdnjs is the curated, exact-version option. jsDelivr and unpkg expose essentially all of npm. Google Hosted Libraries covers only a small set of very popular libraries. ## **Using SRI With cdnjs Correctly** Subresource Integrity lets the browser refuse a cdnjs file whose bytes do not match a hash you declared. The cdnjs website copies a ready-made script element with an SHA-512 integrity value, a crossorigin attribute set to anonymous and a no-referrer referrer policy. Keep all three. Without the crossorigin attribute, the browser fetches the file in no-cors mode, cannot verify the opaque response and blocks the script. 1. Pin an exact version in the URL. SRI and floating versions are mutually exclusive. 2. Take the hash from the cdnjs API or UI, or compute it yourself from the exact file bytes using SHA-384 or SHA-512. 3. Add a Content Security Policy that allows the cdnjs hostname in script-src, so an injected script from any other host still fails. 4. Store the hash in version control next to the URL so a reviewer can see any change in a diff. ### Automating SRI with the cdnjs API The cdnjs REST API returns library metadata, the version list, file paths and the SRI hash for each file. A CI job can query the libraries endpoint for a given library and version, request the SRI field, and render the URL and integrity value into templates. The job should fail when a hash for an already-pinned version changes. A published version's bytes should never change, so a changed hash means something upstream is wrong. ### What SRI does not protect against SRI proves a file has not changed since you hashed it. It says nothing about whether the version you chose was safe. A compromised release, published upstream and picked up by the bot, gets a perfectly valid hash. Review the changelog and diff before you bump a pin, just as you would for a lockfile change. ## **Version Pinning on cdnjs** cdnjs URLs always contain an exact version. There is no semver range syntax and no supported "latest" alias in the URL path. This is the main behavioral difference from jsDelivr and unpkg, and it is intentional: an exact URL is immutable, cacheable for a year and compatible with SRI. The cost is that upgrades are manual. You change the version in the URL, update the hash and redeploy. For teams without a bundler, a small manifest file listing library, version, file and hash, regenerated by a scheduled job that opens a pull request when upstream releases appear, gives you dependency-bot-style updates with human review. ## **The Real Cost of a Third-Party Script Origin** A cdnjs script only wins on latency if the cdnjs edge is much closer than your own origin. Loading it from a new origin costs a DNS lookup plus one round trip each for TCP, TLS 1.3 and the request itself. An already-open HTTP/2 connection to your own origin costs one round trip. Worked example, using arithmetic rather than measurement: - Your HTML is served from a CDN 50 ms away, and cdnjs is also 50 ms away. A cold cdnjs fetch costs about 3 ร— 50 = 150 ms plus DNS. The same file on the existing first-party connection costs about 50 ms. Self-hosting saves roughly 100 ms or more. - Your HTML comes from a distant origin at 150 ms, and cdnjs is 15 ms away. A cold cdnjs fetch costs about 45 ms plus DNS, against 150 ms first-party. cdnjs saves roughly 100 ms. As a rule of thumb, cdnjs is faster when three times the cdnjs round trip time plus DNS is less than the round trip to wherever your page's other assets come from. A preconnect hint hides part of the handshake cost, but it does not remove the extra connection's congestion-window warm-up. ## **cdnjs vs jsDelivr, unpkg and Self-Hosting** cdnjs and jsDelivr differ mainly in scope and version handling. cdnjs serves a curated index at exact versions with SRI hashes surfaced in its UI and API, on Cloudflare alone. jsDelivr serves any npm package or GitHub release, resolves semver ranges, can combine files into one response, and runs on several CDN providers behind one hostname. | Dimension | cdnjs | jsDelivr | unpkg | Self-hosted bundle | | --- | --- | --- | --- | --- | | Coverage | Curated index, reviewed entry | Any npm package or GitHub release | Any npm package | Whatever you install | | Version resolution | Exact only | Exact, ranges, latest | Exact, ranges, latest | Lockfile | | SRI workflow | Hashes in UI and API | Hashes via API, exact versions only | Compute yourself | Not needed (first party) | | Infrastructure | Cloudflare | Multi-CDN | Single provider | Your CDN of choice | | File combination | No | Yes | No | Yes, plus tree-shaking | | Honest limitation | Manual upgrades, propagation lag | Floating versions tempt teams to skip pinning | No SRI tooling, single provider | Requires a build pipeline | Pick cdnjs for reviewed, exact-version libraries with ready-made SRI, jsDelivr when you need breadth or semver, and a self-hosted bundle whenever you already have a build step. ## **What Breaks: cdnjs Failure Modes and How to Confirm Them** Most cdnjs incidents are integration mistakes rather than outages, and each one leaves a distinct signature in the browser console or network panel. | Failure | How it shows up | How to confirm | | --- | --- | --- | | Integrity mismatch | Console reports no valid digest in the integrity attribute, and the script is blocked | Re-hash the exact downloaded file; check you hashed the minified file you actually reference | | Missing crossorigin attribute | Same integrity error, even though the hash is correct | Network panel shows a no-cors request; add crossorigin set to anonymous | | Version not yet published | 404 right after an upstream release | Check the version list in the cdnjs API for that library | | CSP rejection | Console reports a script-src violation | Read the CSP violation report; add the cdnjs host explicitly | | Network-level block or provider incident | Some users, often on corporate or national networks, see an unstyled or broken page | Real-user monitoring errors grouped by network; resource timing entries that never complete | Integrity and CORS errors account for most cdnjs breakage, and both are visible in the console within seconds of a deploy. For scripts the page cannot run without, add a guard: check whether the library's global exists after load, and if not, inject a first-party copy. Because cdnjs depends on a single provider, availability is something you instrument yourself rather than assume. ## **When to Use cdnjs, Bundling or Self-Hosting** - **Marketing sites, CMS themes, legacy apps:** cdnjs with exact versions, SRI and CSP. - **Prototypes and demos:** cdnjs or jsDelivr, whichever already carries the library. - **Bundled SPAs:** self-host through the build pipeline. A public CDN only adds a connection. - **Compliance-sensitive or revenue-critical platforms:** self-host on a CDN zone you control, so that logs, headers and purge are yours. Self-hosting on your own zone is a pull-caching setup. BlazingCDN's [**Anycast CDN for self-hosted JavaScript assets**](https://blazingcdn.com/anycast-cdn/) includes origin shield, request coalescing and Brotli and zstd compression on every plan. It serves over HTTP/2 rather than HTTP/3. ## **FAQ: cdnjs and Public JavaScript CDNs** ### Is cdnjs free to use in production? Yes, cdnjs is free and open source, with delivery sponsored by Cloudflare, and production use is allowed. There is no contract and no service-level commitment, so treat it as a dependency you monitor yourself. For scripts a page cannot function without, pin exact versions, use SRI and keep a first-party fallback copy that loads if the cdnjs request fails. ### Is cdn js the same thing as cdnjs? Usually, yes: people searching "cdn js" mean either cdnjs specifically or a JavaScript CDN in general. cdnjs is one named project, hosted at cdnjs.cloudflare.com, that serves a curated library index. Other JavaScript CDNs include jsDelivr, unpkg and Google Hosted Libraries, which differ in coverage, version resolution and how much of npm they expose. ### Does cdnjs support latest or semver version URLs? No, cdnjs URLs always reference an exact library version, with no range syntax and no supported latest alias. That keeps every URL immutable, cacheable for about a year and compatible with Subresource Integrity. If you need range resolution, jsDelivr and unpkg offer it, but floating versions cannot be paired with an integrity hash. ### Which SRI hash algorithm does cdnjs use? cdnjs publishes SHA-512 integrity hashes in its website snippets and through its API. Browsers accept SHA-256, SHA-384 and SHA-512 and use the strongest algorithm listed. Always pair the integrity attribute with crossorigin set to anonymous. Without it, the browser cannot verify the cross-origin response and blocks the cdnjs script even when the hash is correct. ### cdnjs vs jsDelivr: which should a new project use? Choose cdnjs for a curated library at exact versions with SRI hashes ready to copy. Choose jsDelivr for packages cdnjs does not carry, semver ranges, file combination or GitHub-hosted files. If the project has a bundler, neither is usually the right choice, because self-hosting removes a third-party connection from the critical path. ## **Measure Your cdnjs Connection Cost This Week** Open the Resource Timing data in your real-user monitoring and split every cdnjs request into DNS, connect, TLS and time to first byte. Then compare the total against the same file served from your own HTML origin, on a connection that is already open. If the cdnjs connection overhead exceeds the round trip to your own CDN for most users, move those libraries into your bundle or onto your own zone. While you are there, audit every cdnjs tag for an exact version, an integrity value and the crossorigin attribute. If you decide to self-host and want one zone for scripts, images and larger downloads, the [**BlazingCDN features overview**](https://blazingcdn.com/features/) lists what every plan includes, from purge and cache warm-up through the API to Prometheus metrics. 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The CDN for video and large traffic Their monthly bill vs ours - 20 TBFastly $2,087**$92.50** - 50 TBCDN77 $990**$215** - 200 TBCloudFront $11,965**$765** Published list prices, Aug 2026 [Calculate your cost](https://blazingcdn.com/cdn-cost-calculator/?utm_source=blog&utm_medium=sidebar&utm_campaign=blog_sidebar&utm_content=compare_calc) ## Related posts [![](https://blog.blazingcdn.com/hubfs/Gemini-Blog/image-Oct-17-2026-07-30-22-3464-AM.jpeg)](https://blog.blazingcdn.com/en-us/mp4-vs-webm-best-video-format-for-web-playback?hsLang=en-us) Learn ### [MP4 vs WebM: Best Video Format for Web Playback](https://blog.blazingcdn.com/en-us/mp4-vs-webm-best-video-format-for-web-playback?hsLang=en-us) For web playback in 2026, ship MP4 (H.264 video, AAC audio) as the universal baseline and add WebM (VP9 or AV1) as a ... Oct 17, 2026, 9:32:40โ€ฏAM [Read more](https://blog.blazingcdn.com/en-us/mp4-vs-webm-best-video-format-for-web-playback?hsLang=en-us) [![](https://blog.blazingcdn.com/hubfs/Gemini-Blog/image-Oct-17-2026-07-00-35-8728-AM.jpeg)](https://blog.blazingcdn.com/en-us/cdn-compression-performance-brotli-vs-gzip?hsLang=en-us) Compare ### [Brotli vs Gzip Compression: Real CDN Performance Compared](https://blog.blazingcdn.com/en-us/cdn-compression-performance-brotli-vs-gzip?hsLang=en-us) The brotli vs gzip choice depends on where compression runs. Pre-compressed at quality 11, Brotli typically makes ... 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All rights reserved. ```json { "@context" : "https://schema.org", "@id" : "https://blazingcdn.com/#organization", "@type" : "Organization", "description" : "High-volume CDN for video, live streaming, OTT/IPTV, software, games, SaaS and large-file delivery.", "logo" : { "@id" : "https://blazingcdn.com/#logo", "@type" : "ImageObject", "height" : 560, "url" : "https://blazingcdn.com/wp-content/uploads/2024/08/logo-560-560.png", "width" : 560 }, "name" : "BlazingCDN", "sameAs" : [ "https://www.linkedin.com/company/blazingcdn", "https://x.com/BlazingCdn", "https://www.reddit.com/r/BlazingCDN/", "https://www.wikidata.org/wiki/Q141711074" ], "url" : "https://blazingcdn.com/" } ``` ```json { "@context" : "https://schema.org", "@id" : "https://blog.blazingcdn.com/#website", "@type" : "WebSite", "inLanguage" : "en-US", "name" : "BlazingCDN Blog", "publisher" : { "@id" : "https://blazingcdn.com/#organization" }, "url" : "https://blog.blazingcdn.com/" } ``` ```json { "@context" : "https://schema.org", "@id" : "https://blog.blazingcdn.com/en-us/cdnjs-javascript-libraries-why-developers-still-love-it-2025#article", "@type" : "BlogPosting", "author" : { "@id" : "https://blog.blazingcdn.com/en-us/author/blazingcdn#person", "@type" : "Person", "description" : "Vadym Borovskyi is Chief Product and Marketing Officer at BlazingCDN, where he has led product strategy and growth since 2021. He has more than 11 years of experience in IT product management and B2B marketing. On this blog he writes about CDN pricing and egress costs, video and software delivery, cache configuration, and how teams evaluate and switch CDN providers. He is based in Warsaw, Poland.", "image" : "https://143144902.fs1.hubspotusercontent-eu1.net/hubfs/143144902/vadym-borovskyi.jpg", "jobTitle" : "Chief Product and Marketing Officer", "knowsAbout" : [ "Content Delivery Networks (CDN)", "CDN pricing", "Video streaming delivery", "Software and game distribution", "Cache optimization", "Product Management", "B2B Marketing", "Digital Marketing", "Pay Per Click Marketing (PPC)", "Google Ads", "Search Engine Marketing (SEM)", "Marketing Strategy", "Artificial Intelligence (AI)", "Cloud Management", "SaaS Development", "IT Consulting", "Computer Networking", "Project Management", "Startups" ], "name" : "Vadym Borovskyi", "sameAs" : [ "https://www.linkedin.com/in/axelt/" ], "url" : "https://blog.blazingcdn.com/en-us/author/blazingcdn", "worksFor" : { "@id" : "https://blazingcdn.com/#organization" } }, "dateModified" : "2026-10-18T07:03:08Z", "datePublished" : "2026-10-18T07:03:08Z", "description" : "What cdnjs is, how libraries get added, how it is cached and served, and when to use cdnjs versus bundling or other public CDNs.", "headline" : "cdnjs Explained: How the Public JavaScript CDN Works", "image" : "https://143144902.fs1.hubspotusercontent-eu1.net/hubfs/143144902/Gemini-Blog/image-Oct-18-2026-07-00-43-6295-AM.jpeg", "inLanguage" : "en-us", "isPartOf" : { "@id" : "https://blog.blazingcdn.com/#website" }, "mainEntityOfPage" : { "@id" : "https://blog.blazingcdn.com/en-us/cdnjs-javascript-libraries-why-developers-still-love-it-2025", "@type" : "WebPage" }, "publisher" : { "@id" : "https://blazingcdn.com/#organization" }, "wordCount" : 2232 } ``` ```json { "@context" : "https://schema.org", "@id" : "https://blog.blazingcdn.com/en-us/cdnjs-javascript-libraries-why-developers-still-love-it-2025#breadcrumb", "@type" : "BreadcrumbList", "itemListElement" : [ { "@type" : "ListItem", "item" : "https://blog.blazingcdn.com/en-us", "name" : "Blog", "position" : 1 }, { "@type" : "ListItem", "item" : "https://blog.blazingcdn.com/en-us/cdnjs-javascript-libraries-why-developers-still-love-it-2025", "name" : "cdnjs Explained: How the Public JavaScript CDN Works", "position" : 2 } ] } ``` ```json { "@context" : "https://schema.org", "@id" : "https://blog.blazingcdn.com/en-us/cdnjs-javascript-libraries-why-developers-still-love-it-2025#faq", "@type" : "FAQPage", "mainEntity" : [ { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Yes, cdnjs is free and open source, with delivery sponsored by Cloudflare, and production use is allowed. There is no contract and no service-level commitment, so treat it as a dependency you monitor yourself. For scripts a page cannot function without, pin exact versions, use SRI and keep a first-party fallback copy that loads if the cdnjs request fails." }, "name" : "Is cdnjs free to use in production?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Usually, yes: people searching \"cdn js\" mean either cdnjs specifically or a JavaScript CDN in general. cdnjs is one named project, hosted at cdnjs.cloudflare.com, that serves a curated library index. Other JavaScript CDNs include jsDelivr, unpkg and Google Hosted Libraries, which differ in coverage, version resolution and how much of npm they expose." }, "name" : "Is cdn js the same thing as cdnjs?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "No, cdnjs URLs always reference an exact library version, with no range syntax and no supported latest alias. That keeps every URL immutable, cacheable for about a year and compatible with Subresource Integrity. If you need range resolution, jsDelivr and unpkg offer it, but floating versions cannot be paired with an integrity hash." }, "name" : "Does cdnjs support latest or semver version URLs?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "cdnjs publishes SHA-512 integrity hashes in its website snippets and through its API. Browsers accept SHA-256, SHA-384 and SHA-512 and use the strongest algorithm listed. Always pair the integrity attribute with crossorigin set to anonymous. Without it, the browser cannot verify the cross-origin response and blocks the cdnjs script even when the hash is correct." }, "name" : "Which SRI hash algorithm does cdnjs use?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Choose cdnjs for a curated library at exact versions with SRI hashes ready to copy. Choose jsDelivr for packages cdnjs does not carry, semver ranges, file combination or GitHub-hosted files. If the project has a bundler, neither is usually the right choice, because self-hosting removes a third-party connection from the critical path." }, "name" : "cdnjs vs jsDelivr: which should a new project use?" } ] } ```