# BootstrapCDN: Static and Version-Aligned CDN Links for Bootstrap
> jsdelivr/bootstrapcdn provides BootstrapCDN links backed by jsDelivr, plus scripts for maintaining hosted Bootstrap, Bootlint, and Bootswatch files. It suits frontend projects that can either pin stable assets or accept delayed minor-version updates.
**jsdelivr/bootstrapcdn** — Free Bootstrap CDN hosting
- Repository: https://github.com/jsdelivr/bootstrapcdn
- Website: https://www.bootstrapcdn.com
- Stars: 1,373 · Forks: 265
- Language: JavaScript
- License: MIT
- Published: 2026-10-16 · Updated: 2026-10-16 · Language: en
- Canonical page: https://hysenlabs.com/projects/jsdelivr-bootstrapcdn
## What BootstrapCDN Covers and Who Uses It
BootstrapCDN is the public entry point described by the repository as a way to start with Bootstrap, Font Awesome, Bootswatch, and Bootstrap Icons. Its intended users are frontend developers who want asset URLs without installing each frontend package into the application repository. The service site is https://www.bootstrapcdn.com/, while the underlying CDN URLs shown in the README are served from cdn.jsdelivr.net.
The repository is more than a documentation page. Its file layout includes an Express application, Pug views, route modules, configuration files, tests, update scripts, and Docker deployment files. That split matters when evaluating adoption. A page author normally consumes hosted assets, while a maintainer operates the publishing and version-management side of the site.
The hosted library set is not presented as an application framework or a private asset server. It is a catalog and delivery layer for existing npm packages and related frontend assets. Projects that already pin and deploy every dependency themselves may therefore gain little from adopting this service. Projects seeking a shorter path from a Bootstrap release to a browser-ready stylesheet or script gain more.
## Pinned Bootstrap Assets and Delivered Files
The documented delivery path uses standard HTML link and script elements. A pinned URL contains both package name and exact version, such as bootstrap@4.6.0, followed by the path to a distribution file. Bootstrap styles come from dist/css/bootstrap.min.css, while the JavaScript example uses dist/js/bootstrap.bundle.min.js, which the README identifies as the bundle with Popper.
The README explicitly states that a static version such as 4.6.0 is safe to use with Subresource Integrity. It also warns that a dynamic URL cannot use an SRI hash because the next update changes the referenced file. This creates a clear operational split. Teams that require verifiable bytes should pin a version and manage integrity data. Teams that want automatic minor updates must accept that the original SRI value will stop matching.
BootstrapCDN does not replace the packages themselves. BootstrapCDN determines where those files are requested from. It also gives links to Font Awesome, Bootswatch, and Bootstrap Icons through the main site, although the README provides complete examples only for Bootstrap CSS and JavaScript.
## BootstrapCDN Version Aliases and Their Update Delay
A second documented mode replaces the full patch version with a major-version alias. In the Bootstrap example, bootstrap@4 points to the newest available v4 asset. The README warns that this path can update as new v4 versions become available and may lag by as many as seven days.
This mechanism is convenient when the objective is receiving compatible minor releases without editing URLs. It is less suitable when a deployment needs an exact, reproducible build. A change in the remote asset can alter browser behavior after code has already been deployed. The documented seven-day maximum delay also means the alias is not an immediate view of the newest npm publication.
The version API provides a way to inspect which versions and tags are available:
```text
https://data.jsdelivr.com/v1/package/npm/bootstrap
```
The response shown in the README contains fields such as "latest", "previous", and "next", plus a "versions" array. That endpoint can support an automated update process, but the repository does not document a complete rollback policy, a deployment gate for version promotion, or a client-side compatibility check. Automation consumers still need to define how a discovered version is tested and approved.
## Installing BootstrapCDN Links and Adding the First Page
No package installation is required to consume the documented Bootstrap links. The shortest first use is to copy the pinned CSS and JavaScript URLs from the README into an HTML document. The link element loads the stylesheet, and the script element loads Bootstrap's JavaScript bundle with Popper.
Use this pinned Bootstrap 4.6.0 example when the application must continue requesting the same published files:
```html
```
The README identifies these as example links that pull version 4.6.0. It does not document browser-console behavior or a sample page output, so those outcomes cannot be asserted here.
Developers who want the latest v4 minor version can use the alias form:
```html
```
This version removes the patch number from the URL. Do not reuse an SRI hash generated for the pinned URL, because the alias may resolve to a later file.
## Running the BootstrapCDN Application for Maintainers
Repository maintainers work with Node.js and npm rather than installing BootstrapCDN as a normal public npm package. The package metadata marks bootstrapcdn as private. The README lists Node.js as the only explicit development requirement, while package.json defines the npm tasks used to lint, test, start, and update assets.
Install dependencies from the repository and start the documented development command:
```bash
npm install
npm test && npm run dev
```
The first command installs package dependencies. The second runs the non-functional test set and starts the development process when those tests pass. For a development server that watches CSS, JavaScript, Pug, SVG, PNG, and YAML files, the README also lists:
```bash
npm run dev
# or
npm run watch
```
The production server command is:
```bash
npm start
```
Docker Compose exposes the application on host port 3333 through the `web` service. Its image runs as the unprivileged `node` user, installs production dependencies with `npm ci --omit=dev`, and starts `bin/www.js`. The repository supports self-hosting the BootstrapCDN web application, but this is separate from relying on jsDelivr to serve the assets linked by the public service.
## Asset Updating, SRI Files, and Maintenance Cost
The maintenance workflow is package-oriented. The README instructs a maintainer to replace `package` and `version` in an npm installation command, update config/_config.yml, regenerate integrity values with `npm run integrity`, place the files on S3 and the CDN, and then run `npm run all`. It also requires checking the frontend for visual breakage.
The documented package update sequence is:
```bash
npm i package@version -ED
npm run package version
```
Here, `package` and `version` are placeholders that the maintainer replaces with the target package and release. The repository also exposes task names such as `bootstrap`, `bootswatch`, `bootlint`, `generateFiles`, and `sri`, but the excerpt does not document the arguments or behavior of every individual task.
config/_files.yml contains the CDN files hosted by the application, and its SRI values are regenerated through `npm run integrity`. This creates ongoing work beyond changing a URL: the maintainer must synchronize package metadata, publish files, recompute integrity information, run lint and test tasks, and perform a frontend review. The MIT license covers this repository. It does not replace or clarify the separate licenses of Bootstrap, Font Awesome, Bootswatch, Bootstrap Icons, or other hosted packages, so those assets require their own license review.
The repository is not archived. Its last push was on 2026-06-20. That date confirms recent recorded repository activity, but the README does not promise release cadence, service-level commitments, or a support window.
## Where BootstrapCDN Falls Short and What to Use Instead
The first limitation is version control. Pinned URLs support SRI and reproducibility, but automated updates require an external process to discover, test, and approve a version. The repository documents the jsDelivr version API, yet it does not document rollback behavior. A team that requires internal approval gates should not treat the API example as a complete deployment workflow.
The second limitation is dependency on an external delivery path. The documented links request files from cdn.jsdelivr.net, so users depend on that host and domain for asset availability. The repository's Dockerfile can run the BootstrapCDN site itself, but no procedure is given for configuring those browser-facing links to use a private S3 or CDN origin. Self-hosting the application does not automatically remove the public jsDelivr URLs.
A real alternative is to install Bootstrap and Font Awesome through the application's npm dependency workflow, then bundle or copy the approved distribution files into the project's own deployment. That approach changes ownership. Version selection belongs to the application's lockfile and build, assets can be served from the same origin as the application, and rollback follows the normal release history. BootstrapCDN instead reduces link preparation and supports major-version aliases, but gives up exact-byte control when a dynamic path is used. The right comparison is therefore between CDN convenience and deployment ownership, not between two implementations of the Bootstrap component library.
## Conclusion
Adopt BootstrapCDN when a small frontend needs ready-made Bootstrap CDN URLs and you are comfortable delegating delivery to jsDelivr. Do not choose it when you need private asset hosting, guaranteed immediate version promotion, or rollback procedures that the repository does not document. Before adoption, verify the exact asset version, SRI policy, third-party asset licenses, and whether the aliasing delay fits the release process.
## FAQ
### How do I add BootstrapCDN to an HTML page?
Copy the documented Bootstrap CSS link and JavaScript bundle script into the page. The README shows pinned URLs for bootstrap@4.6.0 as well as aliases that select a v4 release.
### Can I use SRI hashes with BootstrapCDN?
The README says static versions such as 4.6.0 are safe for SRI use. It explicitly says not to use SRI hashes with dynamic URLs because a later update will break the hash.
### How does BootstrapCDN handle version updates?
A major-version alias such as bootstrap@4 resolves to the latest available v4 version, with an update delay of up to seven days according to the README. The jsDelivr package API can also be used to list available versions and tags.
## Sources
- [Issues](https://github.com/jsdelivr/bootstrapcdn/issues)
- [jsdelivr/bootstrapcdn on GitHub](https://github.com/jsdelivr/bootstrapcdn)
- [License: MIT](https://github.com/jsdelivr/bootstrapcdn/blob/master/LICENSE)
- [Project website](https://www.bootstrapcdn.com)
- [README](https://github.com/jsdelivr/bootstrapcdn/blob/master/README.md)
---
Hysen Labs editorial analysis, written from the project's own repository and release notes. Cite the canonical page: https://hysenlabs.com/projects/jsdelivr-bootstrapcdn