Cloudflare has opened a new way to fetch only the needed parts of large files from an origin server. Site owners serving video, downloads or software packages through Cloudflare can enable Origin Range Requests in a Cache Rule. Check that your origin supports partial-file responses and test a real download before rolling it out widely. Ordinary small web pages do not need this setting.
What changed?
A range request asks for part of a file, rather than the whole thing. A video player might request the section around a viewer’s seek point. A download tool might request only the part needed to resume an interrupted transfer.
Cloudflare announced on October 23 that customers on all plans can now turn on Origin Range Requests themselves. Cloudflare says its edge can fetch missing pieces in cache-aligned chunks and combine them with pieces already stored. Customers no longer choose a range size. The company says this can avoid transferring much more data than the viewer requested.
This is not a blanket speed guarantee. Cloudflare reports that its own R2 storage workload saw roughly half the previous 99th-percentile time to first byte after migration. It also reports about 6% less tiered-cache traffic for R2 and similar workloads after a later improvement. Those are Cloudflare’s measurements, not a promise of the same gains for every website.
Who should consider it?
The feature is aimed at large, seekable files such as MP4 video, resumable downloads, archives and package repositories. It is not enabled by default for any file extension, according to Cloudflare’s Cache Rule documentation. Cloudflare says Cache Reserve does not support it.
Turning it on does not make private or otherwise uncacheable content cacheable. Cloudflare may generate partial origin requests for eligible GET requests even when it does not store the response. The origin must handle byte ranges consistently to avoid a full-file fetch; if it ignores the Range header and returns the whole file, Cloudflare may have to download the whole object. Cloudflare’s file-size limits still apply to the full file.
What should you do?
- Pick the right files. Identify a narrow set of public, large-file URLs with real partial-download traffic. Do not apply a broad caching rule to account pages or personalized content.
- Check the origin. Confirm the server or storage service responds correctly to range requests and keeps file versions consistent during a download. Record its current bandwidth and error rates.
- Enable a targeted Cache Rule. In Cloudflare’s dashboard, open Caching → Cache Rules and set Origin Range Requests to On for that traffic. Cache Rules require the domain’s DNS record to be proxied through Cloudflare.
- Test, compare and roll back if needed. Seek through a video or resume a download. Check that a valid partial response returns HTTP 206 and the correct Content-Range. Compare origin traffic and failed requests before expanding the rule. Turn the rule off if your origin cannot support it.
Sources: Cloudflare’s launch and engineering account; Cloudflare’s setting and limitations.
Image: film-strip photograph by LoMit, CC BY 4.0; cropped for page layouts. The film is an analogy for requesting sections of a file, not a Cloudflare product image.
