Convert PDF to MOBI Portable Document Format ↔ Mobipocket Free Online Secure
Your PDF is read here in your browser and written out as MOBI. A PDF records where each letter sits, not what it means, so the headings, paragraphs, lists and tables are worked out from position and size — and you get something you can edit again, not a picture of a page.
Convert your file
Drop a PDF here, or choose one.
Your file never leaves this device. Everything runs in your browser.
Nothing uploaded
Where these formats come from
An EPUB is, underneath, a zipped website: pages of HTML with a stylesheet and a table of contents. That is why text in an e-book reflows — the reader chooses the type size and the words rearrange themselves, exactly as they do in a browser window. MOBI came from Mobipocket, a French company Amazon bought in 2005; it became the first Kindle format and was retired by Amazon in 2022 in favour of EPUB. The contrast with PDF is the whole story of this family: a PDF holds fixed pages, laid out once and never moved, while an e-book holds text that has no pages until a reader opens it.
Where you meet them
EPUB is what every e-reader except the Kindle expects, what public libraries lend, and what most publishers produce. MOBI is for older Kindles and for archives of books bought before the change. Converting a PDF into either is the usual way to get a report, a manual or an out-of-print scan onto a reading device where the text can be made larger.
Questions people ask
Why does my PDF look messy after converting to EPUB?
Because the two work in opposite ways. A PDF knows where every word sits on a fixed page; an EPUB has to be told what is a heading, what is a paragraph and what order it all comes in, and none of that is recorded in a PDF. The converter infers it from position and size, and does well with plain single-column text. Two columns, footnotes, headers repeated on every page, tables and figures with captions are where the guessing shows, and they usually need tidying by hand.
Should I still use MOBI?
Only for an old device that cannot read anything else. Amazon stopped accepting MOBI for sending documents to Kindle in 2022 and now wants EPUB, which modern Kindles handle directly. If you are choosing today, choose EPUB: it is the format libraries lend, publishers produce and every reader but the oldest understands.
Does the file lose quality?
It depends on what the two formats can hold. Converting between formats that store the same thing — a PNG to a BMP, a WAV to a FLAC — loses nothing. Converting into a format that throws information away to save space, such as JPEG or MP3, loses a little every time, and converting back does not bring it back. Where a choice exists, this page errs towards keeping the original quality rather than making the smallest file.
Is my file uploaded anywhere?
No. The conversion happens inside your browser, on your own machine; the file never leaves it and there is no server here that could receive it. That is why a large file is limited by your own memory rather than by an upload, and why nothing you convert can appear in anybody's logs — including ours. The audio and video tools do fetch their conversion engine from this site the first time you use them, some thirty megabytes once; after that the work still happens entirely on your machine.
Why people convert PDF to MOBI
A PDF is a page, and a page has a fixed size. That is wonderful for a contract and miserable for a novel on a small screen. You have to zoom in, drag the page sideways and zoom out again to find your place, and the text never settles into something comfortable to read. MOBI is an e-book format, the old Kindle format, that holds the text as a flow: the reader fits the lines to the screen, the type can be made larger or smaller, and the book looks right on a device built for reading. That is the reason people convert PDF to MOBI: they want a long text to be readable on a Kindle or a similar e-reader.
The people who do it are easy to picture. Someone who owns an older Kindle and has a book or an article as a PDF. A reader whose e-reader software only understands MOBI. A student who wants to carry papers on a device with a long battery life and a screen that is gentle on the eyes. In each case the words matter and the page layout does not.
This page converts PDF to MOBI in your browser. Your PDF is not uploaded to a server, which matters for manuscripts, study material and anything you would rather keep to yourself. Below you will find how it works, what comes across, what does not, and a piece of advice that may save you the trouble: for most readers today, EPUB is the better file.
Before you start: MOBI is an old format
Amazon stopped accepting MOBI in 2022
Worth knowing: Amazon stopped accepting MOBI in 2022, and Kindle takes EPUB now. Unless something specifically needs MOBI, the EPUB is the better file. A Kindle app or a recent Kindle device will happily take an EPUB, and EPUB keeps pictures, which MOBI from this page does not. If you are not sure which you need, try PDF to EPUB first.
When MOBI is still the right answer
Some older Kindle models and some third-party reading programs only understand MOBI. If you own such a device, or a piece of software that insists on it, this conversion is what you need. The file made here is readable on Kindle hardware and software going back many years.
How the conversion works
The structure is worked out from the page
A PDF records where each letter sits, not what it means. There is no stored notion of a heading, a paragraph or a list. Your PDF is read inside your browser, and for each page the converter collects the text with its positions and sizes and decides what is what. A larger line is likely a heading. Lines that follow one another with an ordinary gap form a paragraph. Rows that begin with bullets or numbers form a list. The result is written out as a MOBI in which those headings, paragraphs and lists are real elements.
Reflowable text
The text is stored as reflowable text in the old Kindle format. It reads properly at any type size on any reader that understands the format. Make the type larger and the lines re-break; the text fits the width of the screen without zooming or dragging.
Why this is better than a PDF on a small screen
A PDF page is a picture of a printed page. On a six-inch screen, a full A4 page is shrunk until the letters are tiny, or magnified until you see a quarter of it at once. A reflowable file has no page to shrink. It adapts to the screen you are holding.
What is kept
Headings, paragraphs, bold and italic
Headings, paragraphs, bold and italic are carried across. The text reads in the same order as on the page, and emphasis is preserved where it can be recognised.
Lists
Lists come out as lists, so the structure of your document is not lost on the way to the reader.
A file that Kindle hardware reads
The MOBI is readable on Kindle hardware and software going back many years, which is the main reason to choose this format over a newer one.
What is not carried over
Pictures do not survive
Pictures do not survive this conversion. MOBI refers to images by their position in the record list of the file, and writing that correctly is beyond what this tool does, so leaving them out is better than pointing at the wrong thing. If the pictures matter, choose PDF to EPUB, which keeps them.
Tables are flattened
Tables are flattened. Their text is kept, but the grid is not, so a table is read as lines of text. For documents in which tables are important, MOBI is not the right container.
The book arrives as one chapter
The book arrives as one chapter. A PDF does not record where its chapters begin, and guessing from headings would be wrong often enough to be worse than not guessing. You can still read through the whole text, and your reader will remember your place.
Layout, columns, headers and footnotes
Page layout, columns, headers and footnotes are dropped. A page set in two columns comes out with the columns interleaved, because the lines are read across the page as they sit.
Scanned PDFs yield nothing
A scanned PDF holds a picture of text, not text. From one of those, nothing comes out. Recognising letters in an image is a different job, called optical character recognition, and this conversion does not do it.
How to convert PDF to MOBI here
Add your PDF
Drop the PDF onto the page or pick it from your device. It is opened inside your browser and is not uploaded.
Convert
Press the button. A short document takes a few seconds, and a long book takes longer. Leave the page open until it finishes.
Download and transfer
Download the MOBI and open it in your reading software or copy it to your e-reader. Read the first pages and make sure the text flows as you expect.
A closer look at PDF and MOBI
Fixed and flowing
A PDF is fixed: the position of every letter is part of the file. A MOBI is flowing: it states what the content is, and the reader decides how to lay it out. These two ideas are almost opposite, which is why a conversion has to rediscover the structure that the PDF never recorded. When the source is a clean text document, the result is a pleasant book. When the source is untidy, it can feel like a long stream of text, and that is the honest outcome.
A short history of MOBI
MOBI began with a small company that made reading software for early handheld computers and was later bought by Amazon. For years it was the format of Kindle books. Then Amazon moved to newer formats, and in 2022 it stopped accepting MOBI uploads altogether. The format lives on in older devices and in many people's libraries, which is why conversion to it is still asked for.
What makes a PDF convert well
A plain text document with ordinary paragraphs converts cleanly: a novel, an essay, a report. A document designed with sidebars, text boxes and multiple columns converts poorly. When you convert PDF to MOBI, prefer books and articles to magazines and brochures.
Common situations in detail
Reading a book on an older Kindle
A book you hold as a PDF can be turned into something an older Kindle handles well. Convert PDF to MOBI, copy the file to the device and the text fits the screen at the size you choose.
Studying with a long-lasting screen
Lecture notes, papers and manuals read comfortably on an e-reader, which can run for weeks on a charge and does not tire the eyes like a bright screen.
Accessibility
Readers with weak sight benefit from large type and from the option to have the text read aloud on devices that offer it. A reflowable file makes this possible, while a PDF often resists it.
Proofreading a manuscript away from the desk
A writer who exports a manuscript to PDF can turn it into a MOBI and read it on an e-reader. Seeing the text in a different shape often reveals errors that the eye skips on the screen where it was written.
Practical advice before you convert PDF to MOBI
Test whether the text can be selected
Open the PDF in any viewer and try to select a sentence with the mouse. If the words highlight, the file holds real text and you can convert PDF to MOBI with good hope. If you can only drag a rectangle over the page, it is a picture, and no conversion of this kind will find words in it.
Check whether you need pictures
If the document depends on illustrations or diagrams, MOBI from this page will lose them. Choose EPUB, or keep the PDF.
Extract what you need
If you want only a part of a long document, use extract pages from PDF first. A shorter document converts faster and is easier to check.
Check the first and last pages
After you convert PDF to MOBI, look at the beginning and the end. Running headers and page numbers that slipped through are easiest to spot there.
Questions people ask before converting
Should I choose MOBI or EPUB?
Choose EPUB unless something specifically needs MOBI. Kindle takes EPUB now, and EPUB keeps the pictures.
Why are my pictures missing?
Because MOBI refers to images by their position in the record list of the file, and writing that correctly is beyond what this tool does. Leaving them out is better than pointing at the wrong thing.
Why is there only one chapter?
Because a PDF does not record where its chapters begin. The book arrives as one chapter.
Why did nothing come out?
Almost certainly the PDF is a scan. A scan holds a picture of text, not text.
Is my PDF uploaded?
No. The conversion runs in your browser and the document never leaves your device.
Can I go back to a PDF?
Yes. MOBI to PDF turns an e-book into a PDF again.
Choosing wisely when you convert PDF to MOBI
Decide whether you need MOBI at all
If your device or app accepts EPUB, take the EPUB. The conversion to MOBI is worth doing only when the older format is the one that works for you.
Start with the cleanest source you have
A PDF exported from a word processor converts far better than a scan or a copy of a copy. If you can ask the author for the original text, do so.
Keep the PDF
The PDF holds the pictures, the exact layout and the page numbers. Keep it as your reference.
Getting the most from a MOBI on an e-reader
Copying the file to the device
After you convert PDF to MOBI, connect the e-reader to a computer with a cable and copy the file into its documents folder. The device lists it among your books when you disconnect. If the book does not appear at once, restart the reader or wait a moment for it to index its library.
Set the type to your eyes
Readers let you pick the size of the letters, the width of the margins and the spacing between lines. Take a minute to set them before you start. A text that fits you will be read to the end, while one that does not will be abandoned after a chapter.
Mind the title and the author
Library views use the title and author stored in the book. A file made from a PDF may show only its name, so give the file a clear name before you copy it, with the title and the author, and the book will be easy to find among the others.
When the older format limits you
If you run into limits you did not expect, such as missing pictures or a flat table, the cause is the format and not your device. Switch to EPUB when the reader allows it, or keep the PDF for the pages that depend on illustration.
Privacy and handling
Why local conversion matters for books and papers
Manuscripts, study material and private documents are not things you want sitting on a stranger's server. Many online converters upload your file, process it and send back the result, and for a while a copy lives on a machine you do not control. Here your own browser does the work, so the document stays on your device.
What happens when you leave
When you close the page, the converted file disappears from the browser, so download it first. Nothing about your document is kept.
If something goes wrong
The device does not open the file
Make sure the device supports MOBI. Recent Kindle software prefers EPUB, so try that format instead.
The text has odd line breaks
This happens when the PDF was set with hard line breaks. An e-book editor can join the lines, or you can read it as it is.
The page freezes with a large book
Everything runs on your device, and a long book needs memory. Try again on a computer, or convert the book in parts.
Related tools
The same family of tools covers the neighbouring jobs. For the format that current Kindles prefer, PDF to EPUB works in the same way and keeps pictures, and EPUB to PDF goes back. For text you want to edit as a document, there is PDF to DOCX, and for a web page, PDF to HTML. When you want pictures of the pages instead, PDF to PNG is the answer.
A worked example
Say you have an older Kindle and a PDF essay of forty pages. You drop the PDF here and press the button. A few seconds later you download a MOBI, copy it to the device and open it. The text fills the screen at the size you like. The essay arrives as one chapter, the two small figures from the PDF are missing, and you keep the PDF on your computer for the pictures.
A short checklist
Before converting
Check that the PDF is not a scan. Check whether you can use EPUB instead. Keep the PDF safe.
While converting
Stay on the page until the file is ready.
After converting
Open the MOBI, read the beginning and the end and name the file clearly with the title and the author.
Common mistakes
Choosing MOBI out of habit
Do not convert PDF to MOBI just because the format is familiar. EPUB is the better file for most readers today.
Expecting pictures and tables
Pictures do not survive, and tables are flattened. If they matter, choose another format.
Trying it on a scan
A scanned PDF holds a picture of text, so nothing comes out. Check that you can select text before you start.
Your document stays on your device
The conversion happens locally. Your PDF is read by your own browser, rewritten there and handed back as a MOBI. Nothing is uploaded, so no copy ends up on a server and nobody else can read it. For books and papers with private content, that is the safe way to convert PDF to MOBI.
Summary
To convert PDF to MOBI here, drop the document and press the button. Your PDF is read in your browser and written out as MOBI. A PDF records where each letter sits, not what it means, so headings, paragraphs and lists are worked out from position and size. They are kept, with bold and italic, as reflowable text in the old Kindle format, readable on Kindle hardware and software going back many years. Pictures do not survive, tables are flattened and the book arrives as one chapter. Amazon stopped accepting MOBI in 2022 and Kindle takes EPUB now, so unless something specifically needs MOBI, the EPUB is the better file. Nothing leaves your device.