Measured - byte-exact - 2026

Pedulli vs zip

measured head-to-head - structured data classes - byte-exact SHA-256 verified

TL;DR - honest
Classic zip (DEFLATE) is the most universally-supported compressed archive format ever written. Pedulli is a best-of-N racer - several internal coders, smallest byte-exact output kept, with a +1 byte never-worse floor. It beats zip on every measured class and can be run on a finished .zip for additional savings. Universal compatibility belongs to zip; ratio and the never-worse floor belong to Pedulli.

The measured table

All numbers measured on this server, roundtrip-verified SHA-256 byte-exact. Proofs available on request.

Input	zip (DEFLATE -9)	Pedulli (best-of-N)	Δ
1 MiB of zeros	1,062 B	13 B	much smaller (redundant input)
JSON 31 KB	4,837 B	1,265 B	-74%
HTML 161 KB	52,206 B	38,757 B	-25.8%
Apache logs 3.5 MB	326 KB	217 KB	-33.4%
MP4 master 10 MB	9,743,108 B	9,430,108 B	-313 KB
Random bytes 1 MB	1,048,783 B (+207 B)	1,048,577 B (+1 B)	206 B less overhead
Recompress: Pedulli applied to an 89 KB .zip	89 KB	47 KB	-47%

What zip does better (honest)

Universal compatibility. Every operating system since 1989 reads .zip. Pedulli requires the web UI or the API.
Multi-file archive format. .zip is a container of compressed entries with random access; Pedulli is a codec on a single byte stream.
Email-attachment expectation. Everyone knows .zip.

What Pedulli does that zip does not

+1 byte never-worse floor vs zip's +207 on random data.
Best-of-N racing. Tighter on every measured class.
Recompress an existing .zip for additional savings on archives already in cold storage.
Zero data retention. GDPR by design, EU-sovereign.

When to use which

Use zip when emailing files that must double-click open on any OS. Use Pedulli when the bytes you save matter, or to squeeze more out of existing .zip archives - plus the per-file +1 byte never-worse floor.

Run the free trial Pricing / API All benchmarks

More comparisons: gzip - 7-Zip - brotli - zstd