GZIP Decompressor

Open .gz data locally; gzip is a stream format and does not contain a multi-file directory like ZIP.

Choose GZIP file

—Input size

—Output size

—Size change

—Browser support

Choose a fileUses the browser's native Compression Streams API; no file is uploaded.

GZIP Decompressor: Header, CRC & Size Preflight

Inspect the GZIP header, flags, trailer CRC32 and ISIZE before or alongside local browser decompression.

Quick-win evidence

File handling notes

connects ZIP creation/extraction, archive inspection, GZIP, TAR/TAR.GZ extraction, ZIP merging, multi-ZIP extraction, splitting/joining, duplicate detection, renaming, folder summaries, file inventories, and file-type inspection without requiring a file upload where the browser APIs support the task.

Archive and safety boundaries

Browser memory can limit very large files. TAR extraction supports ordinary TAR/USTAR regular files and directories rather than every PAX/sparse/link edge case. Password-protected or uncommon ZIP compression methods can exceed JSZip support. Normalized download paths do not grant arbitrary filesystem write access.

Practical guide and verification

GZIP usually contains one compressed byte stream

Unlike a ZIP archive, a .gz file normally wraps one compressed payload rather than a directory of many independent files. The original filename field can be useful, but it is not guaranteed to be present.

Inspect header and size evidence before trusting the output

The header can reveal compression metadata while the decompressed byte count helps catch an unexpectedly large expansion. Very high expansion ratios deserve caution when the source is untrusted.

Keep the original when metadata matters

Decompression recovers payload bytes; it does not promise to preserve every timestamp, filename convention or application-specific meaning from the original environment.

Treat CRC and size checks as integrity evidence

Where the format exposes integrity fields, matching them is stronger evidence than simply seeing readable output. Integrity checks still do not prove that the original content itself was safe or trustworthy.

Open decompressed files with an appropriate application

The resulting payload may be text, data, an archive member or another binary format. Decompression only removes the GZIP layer; it does not identify or validate every possible payload format.