Quick answer: for converting, compressing, merging, splitting, signing and tidying PDFs, Altto does the job free with no sign-in and no limit, and your files never leave your device. If you need to edit the text inside a PDF directly, run a team document workflow or use certified digital signatures, Acrobat Pro is still the stronger tool.
How Adobe’s free tools work
Adobe offers two different things that both get called “Acrobat”. Acrobat Reader is the free app for opening, filling in, commenting on and signing PDFs. Acrobat online is a set of web tools for jobs such as converting, compressing and merging. Adobe’s own help pages say that, without signing in with an Adobe ID, most of these online tools let you complete one free transaction and download the result once, and that premium tools allow one free transaction every 30 days. Files you process are sent to Adobe’s servers, where Adobe deletes them shortly afterwards if you don’t sign in.
For everything beyond that, Adobe sells Acrobat Standard and Acrobat Pro as subscriptions.
How Altto is different
Altto’s tools run inside your browser tab, on your own computer or phone. Your PDF is never uploaded, there’s no account to create, and there’s no limit on how many files you process or how often. The trade-off is that very large jobs use your device’s own processing power, so an old laptop will be slower than Adobe’s servers.
| Altto | Adobe Acrobat | |
|---|---|---|
| Price | Free, no paid plan | Free Reader app and limited free online tools; Standard and Pro are paid subscriptions |
| Sign-in | Never needed | Most online tools allow one free transaction without an Adobe ID |
| Limits | None | One free transaction per tool without signing in; premium tools one every 30 days |
| Where your file goes | Stays on your device | Uploaded to Adobe’s servers and deleted soon after if you don’t sign in |
| Edit text inside a PDF | No: convert to Word, edit, then back to PDF | Yes, in Acrobat Pro |
| Sign a PDF | Yes, draw, type or upload a signature | Yes, plus certificate-based digital signatures and sending for signature in paid plans |
| Compress to an exact size | Yes, e.g. under 100KB or 1MB | Choose a compression level |
| Remove hidden metadata | Yes, with a preview of what’s inside | Yes, in Acrobat Pro (Redact and Remove Hidden Information) |
Adobe details are from Adobe’s own help pages; plans and limits change, so check their site for the latest. Sources: Adobe: Try Acrobat online services FAQ.
Where Acrobat is the better choice
- Editing the words in a PDF in place. Acrobat Pro lets you change text and images inside the PDF itself. Altto’s route is PDF to Word, edit, then Word to PDF.
- Certified digital signatures and signing workflows. Sending a document to several people for signature with an audit trail is Acrobat’s territory. Altto’s Sign PDF adds your own electronic signature.
- Professional print and accessibility work. Preflight checks, colour management and tagging PDFs for screen readers are things Acrobat Pro does and Altto doesn’t.
- Teams and cloud storage. If you want documents stored online and shared with colleagues, Adobe’s plans include that; Altto deliberately keeps nothing.
Where Altto is the better choice
- Quick jobs without an account. Open the page and go, as many times as you like.
- Private documents. Payslips, bank statements, ID, medical letters and contracts never leave your device.
- Hitting a size limit. Compress PDF can aim for an exact size such as 200KB, and Compress Image can get a photo under 50KB for an upload form.
- Odd jobs. Counting pages in a hundred PDFs, removing hidden metadata, flattening a form or making a PDF black and white, all free.
Which Altto tools replace the Acrobat ones?
The most-used Acrobat online tools all have a free Altto equivalent: PDF to Word, Word to PDF, Compress PDF, Merge PDF, Split PDF, Delete pages, Rotate, Crop, PDF to JPG or PNG, JPG to PDF, PDF to Excel, Sign PDF, Unlock PDF and Add page numbers. See every tool.
Common questions
Is there a free version of Adobe Acrobat?
Is Altto really free with no limits?
Can Altto edit the text in a PDF like Acrobat Pro?
Is Altto safer than uploading to Adobe?
Is Altto connected to Adobe?
Try it with your own file
Free, no sign-up, no daily limit — and nothing is uploaded.
Adobe Acrobat is a trademark of its owner. Altto is independent and not affiliated with, endorsed by or sponsored by Adobe Acrobat. Details about Adobe Acrobat were checked on its website on 5 October 2026 and may have changed since.