How to Convert MOBI to HTMLZ — Quick & Free
Fast, instant MOBI to HTMLZ conversion. No signup required. Just drop your .mobi file and get .htmlz in seconds.
Batch Settings
About MOBI to HTMLZ Conversion
Short answer: yes, you can convert MOBI to HTMLZ online for free, and quality is well preserved with the right settings. Just upload your .mobi file to CocoConvert, pick HTMLZ as the output, and click Convert. The whole process takes seconds.
Now for the details. MOBI is Amazon's Kindle e-book format — widely used for distributing Kindle books. HTMLZ is a widely used file format. Converting between these two formats lets you convert between formats quickly.
Your MOBI file is decoded and re-encoded as HTMLZ. Converting MOBI to HTMLZ maintains high quality with CocoConvert's optimised encoder settings.
CocoConvert runs entirely online — no software to install, no account to create. Your files are encrypted during upload (TLS), processed on isolated servers in Germany, and permanently deleted after 24 hours. It works in Chrome, Safari, Firefox, Edge, and all mobile browsers.
Need to convert more than one file? Free users can do 5 per hour. Pro gets 100 per hour with files up to 5 GB each.
How to Convert MOBI to HTMLZ
- 1
1. Upload MOBI
Drop your .mobi file onto the page (or tap "Browse" on mobile). Add multiple files for batch conversion.
- 2
2. Select HTMLZ
Choose .htmlz from the output dropdown. Settings are pre-configured for best results.
- 3
3. Convert
One click. The server handles all the heavy lifting using FFmpeg and Sharp.
- 4
4. Download
Your .htmlz file is ready. Download it directly or get all files as a zip archive.
What Happens When You Convert MOBI to HTMLZ
Your MOBI file is decoded and re-encoded as HTMLZ.
Your MOBI file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in HTMLZ format
The converted file is ready for download
Format Comparison
MOBI
.mobi file
| Extension | .mobi |
| MIME Type | application/x-mobipocket-ebook |
| Category | eBook |
HTMLZ
.htmlz file
| Extension | .htmlz |
| MIME Type | application/zip |
| Category | eBook |
Should You Convert MOBI to HTMLZ?
When to Convert
- ✓When you need a HTMLZ file
Frequently Asked Questions
Is MOBI to HTMLZ conversion free?
Yes. CocoConvert offers free MOBI to HTMLZ conversion with generous daily limits — 25 minutes of processing time and up to 5 files per hour (250 MB each). Pro plans remove these limits.
How fast is MOBI to HTMLZ conversion?
Most files convert in 2–10 seconds depending on size. Large ebook files may take 30 seconds. Batch jobs process in parallel for maximum speed.
What happens to my files after conversion?
Your uploaded MOBI file and the converted HTMLZ file are both automatically deleted from our servers within 24 hours. They are never shared, sold, or analysed.
Does converting MOBI to HTMLZ lose quality?
Converting MOBI to HTMLZ maintains high quality with CocoConvert's optimised encoder settings.
Can I convert HTMLZ back to MOBI?
Yes, CocoConvert supports HTMLZ to MOBI conversion as well. However, if the original conversion involved lossy compression, converting back won't recover the lost data.
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