r/pdf

Hey people,

My girlfriend started reading on her Kindle and kept converting PDFs and getting books she couldn't read properly. I am a software developer, so she always told me to make her a better conversion tool. For the past month, I dug into why other tools failed, researched how EPUB works, and how I can make it work.

So I built convert2epub.com. It’s free, and no account is needed for normal text conversions, only for the work done converting scanned pdf's. I posted the first version on r/kindle and got 500 upvotes, improved the first version based on the feedback, and now people are saying it's the best tool they have ever used.

Scans that were already read

Publishers often leave recognised text sitting invisibly on top of the page image. Most converters ignore it and hand back a book of photographs. This one finds that layer and uses it.

I tested this with a 300-page novel. The PDF had 426,904 characters of clean text inside it. Other converters ignored those characters and converted it to an EPUB that contained 637. It was a 20MB book of pictures.

That same book now comes out at 1.4MB with real, resizable text.

Formula/Code recognition

Mathematics is set in two dimensions and extraction reads in one, so a fraction arrives as a column of fragments. Equations are kept as drawn while the prose around them still reflows.

Your typography back

The first page becomes the cover, and the title and author are read from the file rather than left as a filename.

Removing watermarks and repeated title/footer.

Every page of a book repeats its title, author and page number in the margin. On paper, you never notice. Extract the text, and those become ordinary lines, so your reader flows them straight into the prose. Same for watermarks and adverts stamped onto free PDFs. In that same book, it was 778 stray lines across four repeating patterns. I added a feature to remove them.

When there is no text to recover, OCR reads the pages instead, in eight languages and only the pages that actually need it.

Hello everyone, I am developing my own PDF editor called KeyPDF. I have been working on it for over a year from scratch, so every new feature is not really dependent on the limitations of third-party software. Therefore, I wanted to ask what kind of features keep you using expensive software. So far, I have implemented text editing and a good level of JavaScript support. I am thinking in the direction of scripts to automate edits or maybe advanced DRM on PDF files. So, if you have any ideas on what kind of advanced features I should add, please let me know.

I have invoices starting with 1_, 2_ etc…
And I want to combine them with the purchase order also starting with 1_,2_ etc..
I have adobe acrobat pro
I’m using my work computer so I can’t download anything else.
Any ideas how to automate it?
Don’t want to do it one at a time because it’s 100’s of files

I have a scan of a digital book, and it’s a long picture with all the pages (around 200) one above the other in original quality each. I need a fast way to cut it up into multiple pages and put them into a single pdf. I also have the original digital book, but it’s protected and i can’t download it, the only way I can think of is screenshotting each page manually but it takes too long for longer books.

People call PDF apps bloated all the time, but curious what makes something feel bloated in day-to-day use. Is it slow startup, random background processes, too many toolbars, popups, updates, AI features getting pushed into basic reading, or just the app trying to do way more than you opened it for?

Where’s the line for you between “useful features” and “why is this thing doing so much”?

A few months ago I noticed I had a ridiculous bookmark folder.

One site to merge PDFs.

Another one to compress them.

Another one to convert images.

Another one because the previous one suddenly wanted me to create an account.

Another one because I'd hit some random upload limit.

So I started building my own tool mostly for myself.

I thought the difficult part would be the frontend.

It wasn't.

The real pain was discovering how weird PDFs actually are. Files that open fine in one library fail in another. Compression sometimes saves 80% and sometimes barely moves the needle. Users upload things you never imagined they would upload.

The project ended up taking way longer than expected, but I learned a lot.

For anyone who's worked on file-processing software: what was the bug or edge case that made you question your life choices?

I’m a medical postgrad and I want to listen to my textbook PDFs (lots of dense clinical text, some tables/images) while commuting or working out.
Looking for recommendations on:
Apps/tools that convert PDF to audio with a natural-sounding voice (not robotic)
Whether OCR is needed first for scanned PDFs

AI tool that might help?

i remember Claude’s website saying it could handle PDFs up to around 1k pages, but a few days ago i tried uploading a PDF that was 2k+ pages just to see what would happen.

surprisingly, it handled it really well.

I was asking questions about pretty specific things buried in the document, and not only did it find the answers, it also gave me the line numbers for where the information came from when I asked. That part is actually super useful for me because I often need to go back to the original PDF and verify the source rather than just trusting the AI answer.

the only thing i really wish Claude had now is a better built-in PDF viewer.

Like imagine if I could click the citation / line number in Claude and it would open the PDF right there, jump to the exact sentence it used, and highlight it. For someone doing finance or research or working with documents where references actually matter, that would make the whole experience sooo much better.

I know it's hard to interpret it just from the title. I mean, whenever I turn on the dark mode of a website or a pdf app I'm reading on, it makes just the interface dark. However, what I need is the actual pages to be switched to dark mode.

Wanted to share something I built after getting annoyed at how many "free PDF tools" quietly upload your file to a server you know nothing about.

SiriTools (siritools.com) runs all of its tools — PDF merge/split/compress/OCR/sign/protect, Word/Excel/PDF conversion, image tools — entirely in the browser tab. Nothing gets sent anywhere, which you can check yourself: open your browser's Network tab while using any tool and you'll see no request carrying your file.

Side effects of that approach: no file size limit, no sign-up wall, and no per-use tracking/analytics on our end either.

Not trying to oversell it — it's just a toolkit for everyday stuff (merging PDFs, converting a Word doc, resizing images), but for anyone who cares where their files actually go, thought this sub would appreciate the approach. I am new to this, so any suggestions for improvement or additional tools would help.

[https://siritools.com\](https://siritools.com)

Like a Kindle, but for PDF in e-ink

I am trying to apply to a job, I used a template on Word, and when I was done I exported to PDF and it saved as an Adobe Reader PDF. However in word the document is 4 pages, in Adobe it is 5 pages. I obviously don't want to send an application with a large nearly empty page but I don't know what's causing the gap? Any suggestions?

Guys I have a pdf with a password which I know the half of , how do I unlock it without the full password?