Due to pdf popularity there is a lot of demand for pdf processing tools. And the format is so complex that there are many nontrivial and creative ways to do pdf processing. That's why these "Hello World" projects usually make Top 5 on HN, and one of the upvotes is usually from me.
Moreover, I see a webapp and I immediately assume everything I do in this app is exfiltrated and abused.
I can check that the webapp advertised above is indeed local-first, but I can't be 100% sure they don't steal my data in a way I did not foresee, e.g. via websockets or cookies.
Because I learnt this the hard way by being on Instagram and Gmail.
Your commands to process PDF with Ghostscript are lossy (they lose lots of metadata and in minor ways they also change how the PDF renders), and they produce very large PDF files.
You're being downvoted because not everyone has CLI access to a server and the required ghostscript binaries etc.
Realistically, most 'normal users' have PDF needs like these links and we as tech people can safely give these sites to non-technical people and have confidence their data isn't being stolen on remote dodgy servers (think gas / electricity bills, invoices, bank statements etc which is a PII gold pot).
Server? what server? Ghostscript is available in virtually any Linux distro, on Mac with and without brew and even on Windows.
I have no confidence in any website, especially the one that claims to be local-only but can technically change on a whim of the developer once it starts getting enough traffic from users.
OTOH, I trust 30+ years old software sitting on on my hard drive not to phone home on every keystroke.
During my college days, I used iLovePDF a lot, so I wanted to build an alternative to it. It’s not just about PDFs - I also have work in progress around image processing and related tools and Chrome Extetion as well
Sure, if they're tested well enough that there are no obvious UX issues (which is usually not the case)
It's just that there's zero effort put into them so they don't really offer anything of value. If you write a todo list-tier app, it would be completely useless to most people, but it's a learning project for you. If you vibecoded a todo list-tier app, it's completely useless to most people including yourself.
So if a platform is vibe-coded, it suddenly has no value? When the Spotify founder vibe-codes an app, it’s praised—but when an open-source contributor like me does it, it’s seen as a bad thing? That doesn’t seem fair
Was this done heavily LLM assisted? Especially the PDF Edit tools have user-interaction quirks and bugs that a human developer would catch immediately during the regular manual testing when developing.
I'd suggest you at least try and mitigate that by having the LLM do extensive e2e testing if you aren't interested in using your own product.
Yeah, and I have the feeling it is not tested at all.
It offers Word -> PDF conversion. Just for interest I tried it and it doesn't even get the simplest page right. It puts the filename into an header. The test page had 4 images, one svg, one pdf (from svg), and another variation of the first 2. The generated PDF only contains 2 of those images with wrong sizes. The later two are missing. So it's basically completely useless.
The free of charge LibreOffice gives much better results with its own caveats.
I don't even care about that. My suggestion to him was earnest.
I don't have a problem with LLMs. Just with how people use them. I just don't like "slop". I see the same user-interaction problems every time.
I just don't want people to litter their heavily polished immaculately styled products that have so clearly bad user-interaction design. E2e testing and closing the loop on LLMs does seem to help here.
Though I really would prefer people click around their own product for at least 5 minutes.
It matters to me. Depending on the ratio there is a line between 'LLM assisted' and 'LLM derived'. There are enough samples of open source code around this theme out there that this could be one of either and the goal to commercialize it is a messy one if the provenance of the code isn't clear. It would be great to see this sort of thing litigated so that there is at least some clarity rather than just a moral stance.
How does it fare with PDFs consisting entirely of images? Any PDF tool was struggling with compressing a passport scan (made with iPhone so might've contributed somehow, knowing Apple and PDFs) I had to cut down in size. Ended up using ImageMagick cause any Ghostscript based tool couldn't get it below 7 MBs from the original 28MB which, although, pretty good, was still too high and I could tell there was still plenty of detail that could be discarded without losing the eligibility of the document. I had to compress it with ImageMagick at the end, cut it down from 28MB to 3MB.
Also does Adobe have some kind of patent/copyright on PDF forms? I don't think I saw any free tools that can edit fillable fields / tables in PDFs. I don't see any mention of forms in the Suite section of your app either. Is it just stupidly difficult / annoying to implement ?
Image-only PDFs (scans):
These are the hardest case. If a PDF is basically high-res images (like iPhone scans), browser-based tools have limits compared to ImageMagick, which has much finer control over resampling and JPEG compression. Ghostscript-style pipelines help, but ImageMagick often wins if you’re willing to discard more detail. Improving this is on the roadmap, but it’s genuinely tough in-browser.
PDF forms:
Adobe doesn’t own forms, but editable PDF forms are extremely complex and poorly standardized. Many free tools avoid true form editing because it’s easy to break files. That’s why I haven’t enabled it yet—possible, just time-consuming and error-prone.
For my hard sci-fi novel, I wanted people to give me feedback by annotating the PDF directly. Since I didn't know what local PDF editors they had available, I decided to vibe-code a web-based PDF annotation editor using PDF.js. (Yes, malicious users could have a field day by guessing the URLs.) It's pretty rough:
Basically, you drop a PDF onto your own web server. The web server serves up PDFs via PDF.js on the client. When the user highlights text to annotate it, the date, time, and text of all annotations in the document are pushed back to the server. As the author, when I reload the same PDF URL, I can add, review, modify, navigate through, or summarize the annotations just like a reader. Here's a screenshot with a funny comment one of my beta readers made:
I wonder why everything now is written in web frameworks. Meanwhile I am currently using macos which has a magnificent PDF tool called... Preview. It allows annotate, merge, realign pages, insert one page from another document or even a JPEG-scan, etc.
However, before the courtesy of my company giving me a macos-enabled gear - I had to cope with PDFs using multiple apps on Windows and Linux. Recently I got there again and found out that PDF support is really weak in Linux, and the formerly award winning Acrobat Reader now looks slow and poor, trying to steal my data and occupy as much space as possible. Also Acrobat Reader reference browser for linux is killed now.
Hence, the question. If everyone is using PDF, why there are no good, fast native tools? and... why are we even staying with PDF?
There are many powerful native pdf tools but they are usually paid and you have to install them. Preview is ok but its only on mac. Preview also has only some of the features.
These online converters are immensely popular for a reason. They also used to do everything serverside and had ads all around which is obviously terrible security wise. So having WASM versions is much better.
Since these are link away they are easy to send and save. I help self-host a podcast and you need very particular settings for the export of the audio file. Instead of cooking up some automated solution, editors have bookmark of this https://ffmpeg-online.vercel.app/ with all the ffmpeg settings correctly selected and they can do the final file themselves for both their preview and production.
Compare that to having multiple people with multiple platforms having to install and learn to use some gui app.
Me and my buddy run a small indie dev studio, and a while back we got frustrated with how most PDF scanner apps feel — clunky UX, subscriptions everywhere, ads, and in some cases your documents get uploaded who-knows-where (for example, incidents reported leaks by TechRadar and Fox News).
So we built our own PDF scanner & editor — lightweight, privacy-first, and (hopefully) not annoying to use. No ads, no subscriptions. Most features are free — a couple of advanced tools require a one-time unlock. All core features run 100% offline with on-device processing.
The main features are built for everyday workflows:
Scan documents — auto edge detect, live corner adjust, batch multi-page
Fill and sign forms — reusable signatures, flatten for secure sharing
OCR text recognition — preserves layout, searchable PDFs or clean text export (supports 18 languages, e.g., English, Spanish, French, German, Italian, Portuguese, etc.)
Edit OCR-detected text — adjust or fix recognised text
Page tools — reorder, rotate, duplicate, delete, extract pages
Annotations and highlights — comments, text notes, custom watermarks
Folder organization — custom folders, drag-and-drop move/rename
Everything runs locally — no accounts, no tracking, no upload processing.
You can download an AI model to your device (one-time download — it stays cached), and then:
- ask questions about a document
- summarise sections or chapters
- extract key points or data
- turn long documents into quick notes
- After the model is installed, all Chat PDF processing happens fully offline on your device.
The app is free to download, and most features are free (scanning, OCR, signatures, annotations, editing, etc).
We wanted to keep the essential tools free, and only charge once for a few advanced features.
We also put together a YouTube playlist with short feature walkthroughs.
We’d really appreciate feedback — especially on the Chat PDF feature (usefulness, speed, UX, edge cases, things it should do better). If you try it and have suggestions, we’re actively improving the app based on user feedback.
I developed an aversion to "with love"-marketing. I've seen too many products come full circle from idealistic "ad-free-forever" "will-never-sell-your-data" "open-source-forever" "customer-first" student-times to selling out everything.
Just to be clear, I’ve been contributing to the open-source community since 2020, and I have no intention of misleading anyone. The use of the word ‘love’ isn’t about branding off another product-it’s simply a tool I personally needed, so I built it. If you’d like, you can also check my GitHub to see my work.
“Sorry about that. Some people jump to conclusions about things they don’t fully understand. I’m just trying to build something useful and contribute to the community, but reactions like this can make it difficult
You’re not, you’re trying to elevate your own profile while having to learn or do as little as possible along the way in order to accomplish that. It’s very transparent in your methodology for this “contribution” and the language you use to talk about it. This is the opposite of a contribution.
After the incident with Tailwind CSS, I decided not to make this open source. Sponsorship has been zero since COVID, so it’s genuinely hard for open-source developers to sustain their work
Sorry don't take this personally but isn't this made with LLMs? Isn't the "incident with Tailwind" the problem that devs no longer support the project because they use it through LLMs often without knowing?
I mean if i understand you are saying you won't release open source code because LLMs would feed/stole it. I get that position. But you are already feeding from the devs that were exploited. Seems a bit hypocritical to use LLMs if you have that stance.
It was always very hard to make money directly from open source. The Tailwind thing (incident??) was only notable in terms of its publicity. The fact that they thought they could make money from code the customer doesn't have to pay for is the incident perhaps?
I'm hoping one of these efforts will lead to local translation of PDFs. Anyone aware of one? Not local, but the best I've found is using Google Translate via camera/images.
Great work, thanks for sharing and congrats on the launch!
Very very small note - many clickable things on your site (the "explore" and "new task" buttons, the directory and blog links at the top, etc.) don't change the cursor to the css "cursor:pointer" (ie the clicky hand)
You might want to add `cursor-pointer` to your tailwind <button> elements
There's a problem with i18n on the landing page, set my browser to German I see things like "home.alternative_title". Tbh I'm not sure such a site needs i18n at all, Claude was a bit overzealous there ;)
well, you just have to undercut Adobe Suite price by 50% and most people would buy your stuff:
Most people mainly use only PDf merge & split & add comments & signing - and pay for this a monthly Adobe subscription of 29,99 USD last time I checked.
Yeah, I’ll do that. I have a Chrome extension that I’m planning to make paid, and I may also release a desktop version. I’m thinking of pricing it cheaply—around $2 for lifetime access
I’m doing everything locally, with no pricing on the extension for now. I do plan to make it paid later, but since all processing happens locally, your files never leave your device and remain completely safe.
also not just PDF the image processing also WIP will be done by next week
makes it difficult to verify that it runs locally. unobfuscated source is not available. important actions, like open a PDF, save edited PDF, will be stuck or error if you cut the internet after opening the site and only unstuck after you reenable internet. I get it's probably for speed
anyway, if you save the page in Chrome and serve it on a local server, it works even with internet disabled, so there's that.
Thanks for pointing this out. You’re right - some assets are currently loaded at runtime, which can cause actions to hang if the internet is cut mid-session. All PDF processing itself happens locally in the browser, and as you noticed, serving the page locally works fully offline. Improving offline behavior and making this easier to verify is on the roadmap
Might be better to provide a downloadable executable instead of asking the user to trust that the browser isn't doing what the browser was designed to do.
I disagree on that. I think that the main value of this kind of tools is "no installation required".
There are already free PDF editors that can be downloaded and installed once forever. What I used most is Libreoffice Draw: it imports a PDF, edit it as if it were a file in its own format, export as PDF again. It's not the only choice. Firefox has had a vanilla PDF editor since last year: download a PDF or drag one inside the browser window, edit it, save it. It's enough to add a PNG of my signature and fill out forms.
Good work! I do like that the tools are task centric and that means I don"t have to handle all sorts of things, I just quickly learn the three to four tools that I really need (as a person working in the real world). #pareto
Now, privacy, I love it! That "normal people" just store stuff in the cloud "it's on my phone", yeah ok, is one thing. It's another topic…
But since Gmail came out and was all the rage in nerd circles, I am wondering why the people who understand the tech the most, are so eager to hand over their data to Big Tech and some other very questionable entities.
Here's the thing in terms of money.
If your app does put my data into the cloud, I am not going to use it. At all. Ever.
If your app blesses me with a beautifully designed native GUI (or UI), instead of presenting itself in Electron slop to me, then I am already almost sold. Literally. I start to consider forking over some cash to you, dear developer of that beautifully designed, privacy respecting app.
I do use my browser to browse the web. I am not interested in a "secondary OS architecture" where I have to play sys admin for a range of "apps" aka plugins. Neither Chrome plugins (I don't use Chromium based stuff.) nor Wordpress plugins, nor Emacs "modes" are going to replace well done native programs.
You don't care enough about your project to provide a native program? Tells me, I shouldn't care either. Good buy.
For a high school student who survives on an allowance, paying $39 for an app may be a bit much, but not for an adult with an income.
Curation. A good maintained app store does all the "sys admin" stuff for me. No viruses, no weird installation procedures and so on.
This is why that works. Hassle-free. Locally-run, native app, means beauty and privacy.
I would pay for that. Happily. In fact, I have done so many times. The success of a plethora of developers with paid-for apps in the stores proves I am not the only one.
And, btw, this is the distribution/commerce model that RMS always favoured. I quote RMS:
> Since “free” refers to freedom, not to price, there is no contradiction between
selling copies and free software. In fact, the freedom to sell copies is crucial: collections of free software sold on CD-ROMs are important for the community, and selling them is an important way to raise funds for free software development. Therefore, a program that people are not free to include on these collections is not free software.
This is basically the app-store model.
And I would pay, for the above stated reasons and I would be inclined to gulp an even higher price if the package has the "OSS inside" sticker on it. For personal reasons, right?
Then there is one last thing. I don't want to have to create an account somewhere just to test-drive your app. Or to use it fully, later on.
Privacy means, I don't have to be online in order to use the software. The end.
Ah, cool idea. I’m currently integrating image processing features—crop, compress, and meme generation. Once that’s almost done, we can move on to integrating the workflow.
