W
Reading your own draft
A manuscript reads very differently on e-ink than in Word, and typos you have stopped seeing on screen tend to reappear.
DOC & DOCX · CHAPTERS FROM YOUR HEADINGS · NO INSTALL
DOC and DOCX to MOBI.
Convert Word documents — .doc and .docx alike — into MOBI files for your Kindle. Plug the Kindle in, copy the file across, and it appears in your library with your heading styles turned into real chapters. Up to 50 at a time.
Convert Word to MOBI
Up to 50 files
Drop DOC or DOCX files here or browse
DOCX
DOCX
DOCX
DOCX
DOCX
+45
Your MOBI files are ready
Converted
MOBI · chapters · no watermark
MOBI
MOBI
MOBI
MOBI
MOBI
MOBI
+ 12 more queued
Upload your documents, get MOBI files back. This is the whole app.
Every conversion is anonymous — we never track who converts what
4.8 / 5
· 10,000+ paid
€1 day pass · €6 yearly · €30 lifetime · no ads, ever
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€1 day pass · €6 yearly · €30 lifetime · no ads, ever
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One account unlocks all 79 AppsCyborg tools
One account unlocks all 79 AppsCyborg tools — convert, compress, download and extract, across video, audio, images, PDF and more. See all tools →
Two steps. That's it.
1
Upload your documents
One file or 50 at once
2
Download the MOBI files
MOBI
novel.mobi
MOBI · no watermark
Grab it within the hour. Download links expire 60 minutes after conversion. Copy the file onto your Kindle over USB — it lands in Documents and shows up in your library. If you would rather email it across, Send to Kindle needs an EPUB these days.
Why a paid converter is the one worth using
Free e-book converters are funded by advertising, and it shows in the limits: one file at a time, a size cap, and a queue. If you are moving a manuscript onto your Kindle, or a folder of chapters, the batch is what you actually need.
50 documents in one pass
A book split into one file per chapter, a term of lecture notes, a whole reading pile. Queue the lot instead of feeding them in one at a time.
Anonymous & private
Unpublished manuscripts stay yours. We don't track who converts what, and files are never handed to third parties.
No watermark, no sign-up wall
Nothing is stamped into your book and nothing is held back for a paid tier. What you download is the file.
Try it for €1
A 24-hour day pass costs €1. No subscription, no auto-renewal — enough to convert a manuscript and check it on the device.
START HERE
Day pass
€1
/ 24 hours
Just need a batch converted today? Unlimited conversions for 24 hours. No commitment.
- Unlimited conversions for 24h
- No subscription, no auto-renew
Yearly
€6
/ year
The price of a coffee, once — for a whole year of conversions.
- Unlimited for 365 days
- Best value if you convert often
Lifetime
€30
once
Pay once, own it forever. Every future format and update included.
- One payment, never again
- All future updates included
Every plan unlocks all 79 AppsCyborg tools — no ads, no watermarks, plus a 7-day money-back guarantee.
How €1 compares to “free”
| Word to MOBI Cyborg | Free online converter | Desktop app | |
|---|---|---|---|
| Files per batch | 50 | 1 | Many |
| File size cap | 200 MB per file | Capped, often 10–25 MB | None |
| Daily conversion limit | None | 1–2 / day | None |
| Nothing to install | Desktop app | ||
| Ad-free & untracked | Ad-funded | ||
| Price | from €1 | Free (ad-funded) | €20–60 |
Free Word-to-MOBI tools exist because advertising pays for them, and the model shows: one file at a time, a size cap, a queue, and an upgrade prompt when you drag in a second. Installing Calibre on your own machine is a genuinely good answer and costs nothing — it is the same conversion engine we run — but it is a desktop program to install, learn and keep updated. Word to MOBI Cyborg starts at €1 for a day, installs nothing, and takes 50 documents at a time at up to 200 MB each.
What lands on the Kindle
MOBI is Amazon's own e-book container, and like every e-book format it reflows: the Kindle decides where lines and pages fall based on the font size you picked, not on how the document looked in Word. So the conversion is about structure, and the structure it builds comes from your heading styles.
50
documents per batch
200
MB per document
60
minutes to download
0
watermarks
Your headings become chapters
TOCHeading 1 and Heading 2 in Word turn into the chapter list the Kindle's menu jumps around with. If you styled your chapter titles as headings rather than just making them bold and big, this works properly.
Copy it across by USB
USBPlug the Kindle into your computer, drop the file into the Documents folder, eject. It appears in your library alongside everything else — no account, no email, no waiting.
DOC as well as DOCX
.docThe old binary format from Word 97–2003 is handled too, with no need to open and re-save it as DOCX first. Both formats go through the same conversion.
Formatting that means something survives
✓Bold, italics, lists, tables and images all carry across, because those describe the text. Margins, page numbers and headers do not, because they describe a page and an e-book has none.
Nothing stamped on it
cleanNo watermark, no advert chapter appended at the end, no banner on the cover. The file is your book and nothing else.
Worth knowing: MOBI is the sideloading format now
MOBI still works on a Kindle, but only one way in. Amazon stopped accepting MOBI through Send to Kindle at the end of 2023, and stopped accepting it for publishing in March 2025, so you can no longer email one to your device or upload one to KDP. What still works — and works well — is the cable: copy the file into the Kindle's Documents folder over USB and it appears in your library. That is the case this tool is for, and it is the right choice for an older Kindle in particular. If you would rather send books wirelessly, convert to EPUB instead and let Send to Kindle do the rest. The other thing to check before converting is your headings: chapter titles need to be styled as Heading 1 or Heading 2, because that styling is what becomes the chapter list.
Sending wirelessly instead of by cable? Send to Kindle takes EPUB and converts it for you.
See it in action
Word to MOBI Cyborg, start to finish · Watch the walkthrough →
A short walkthrough: drop the files in, watch them convert, download the MOBI files. That's the whole tool.
Ready to try it? Create your account above.
Who converts Word to MOBI
Almost everyone here has something long they want to read on a Kindle rather than on a screen they work at:
R
An older Kindle
Devices that predate the newer formats still take a MOBI over the cable quite happily, which keeps a working Kindle working.
P
Sending to beta readers
A reader with a Kindle can drop the file straight on, and it cannot be edited by accident the way a DOCX can.
F
Course notes and handbooks
A long document with proper headings becomes something you navigate by chapter instead of scrolling.
T
Keeping a Kindle library tidy
Converted documents sit alongside bought books with covers and chapter navigation, rather than as loose files.
S
Reading away from the desk
E-ink in sunlight, weeks of battery, and no notifications — the reason people still reach for a Kindle at all.
Whatever it is for, upload your documents and get MOBI files back.
Different format — or a different way in?
Emailing it to the Kindle rather than using a cable? That needs Word to EPUB. Need a fixed page instead of a flowing book — a contract, a form, something to print? Word to PDF. Coming from a PDF or an existing e-book? PDF to MOBI, MOBI to Word and EPUB to MOBI — all included in one account.
Common questions
Getting started
What is Word to MOBI Cyborg?
A web app that turns DOC and DOCX files into MOBI e-books for the Kindle. It reads your heading styles and builds the chapter list from them. Upload up to 50 at a time — nothing to install and no watermark.
Does it work on a phone?
Yes. It works on all Android phones, and on iOS 12 and higher. Conversion happens on our servers, so a phone finishes as fast as a desktop — you only need a browser.
How do I convert Word to MOBI?
Two steps. Drag your documents onto the upload box at the top of this page — up to 50 at a time — then collect the result. One document comes back on its own; a batch comes back as a single ZIP. There is nothing to install and no settings to pick.
Structure, size & batches
How do I get the file onto my Kindle?
Over the USB cable. Plug the Kindle into your computer, open it like a drive, drop the file into the Documents folder and eject — it appears in your library with the rest of your books. What you cannot do any more is email a MOBI to your Kindle: Amazon removed MOBI from Send to Kindle at the end of 2023. For the wireless route, convert to EPUB instead and Send to Kindle will convert it on the way in.
Can I convert old .doc files, not just .docx?
Yes, and you do not need to re-save them as DOCX first. Both formats are accepted and handled by the same conversion.
How many files can I convert at once?
Up to 50 per batch. Each result is named after the document it came from. One document comes back on its own; a batch comes back as a single ZIP.
Is there a file size limit?
200 MB per document, far more than a manuscript needs — you would only approach it with hundreds of high-resolution images embedded. A conversion that somehow runs longer than five minutes is stopped rather than left hanging.
Why does my Kindle show the book as “Unknown”?
Because the document did not carry a title. A MOBI stores its title and author as metadata and that is what the Kindle library displays, not the filename. Word keeps both under File → Info, and they are blank unless you filled them in. When yours is blank we name the book after the file you uploaded so it is at least identifiable, but setting a real title and author in Word before converting is the only way to get them right — and it takes about thirty seconds.
Will my chapters show up in the Kindle menu?
If your chapter titles are styled as Heading 1 or Heading 2 in Word, yes — those become the chapter list you jump around with. If they are just typed in a larger bold font, the converter has no way to tell them apart from ordinary text and you will get a single unbroken book. Applying heading styles is the single most useful thing you can do to a document before converting it.
Should I use MOBI or EPUB for my Kindle?
It depends on how the file gets there. If you are copying it across with a cable, MOBI is fine and this is the tool. If you want to send it wirelessly, you need EPUB, because Amazon stopped accepting MOBI through Send to Kindle at the end of 2023 and stopped taking it for KDP publishing in March 2025. MOBI files already on a Kindle keep working, and sideloading keeps working; it is only the wireless and publishing routes that closed.
Pricing, privacy & limits
How much does it cost?
A €1 day pass gives you 24 hours of unlimited conversions. Yearly (€6) and lifetime (€30) plans are also available (+ VAT). Every plan unlocks all 79 AppsCyborg tools, not just this one.
How long does my download link stay valid?
60 minutes. After that the link expires and the converted files are removed — just re-run the conversion if you need them again.
Do you track or keep my files?
No. We don't run ad or analytics tracking on what you convert, and your files are never sold or shared for marketing. Uploaded documents are processed only to build your MOBI files and are removed once the 60-minute download window closes.
Is there a limit on how often I can convert?
No. While your day pass, yearly or lifetime plan is active you can run as many 50-file batches as you like — there is no monthly quota and no per-conversion charge.
Still have a question?
We usually reply within a day.
Your Kindle files are minutes away.
Create an account and upload your documents — up to 50 at once, chapters built from your headings, no watermark.
Free account
€1 day pass
Anonymous
Creating your account is free — you only pay when you convert
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or sign up with email
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