AnythingOnline

HTTP headers

HTTP byte-range planner

Resolve closed, open-ended and suffix byte ranges against a known length.

Your inputs

Start with an example

Your inputs stay in your browser.

Your result

Example result

How it works

Resolve each requested range, clip its end to length − 1 and identify unsatisfiable entries. Output inclusive Content-Range values.

For 1000 bytes, bytes=0-99,-50 selects 0–99 and 950–999: 150 bytes across two ranges.

Limits

This does not fetch a URL or build a multipart response. Ranges stay separate, so overlapping bytes are counted once per range. If-Range and server range policy are excluded.

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Calculate a Retry-After wait from an explicit UTC reference time.

Utility

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Split Link values, preserve quoted commas and resolve relative targets.

Utility