| Tool | Free Limit | File Size Limit | Platform | Account Required | Legally Binding |
|---|---|---|---|---|---|
| Adobe Acrobat Online | 2 PDFs/month | 2 GB | Browser | Yes | Yes |
| DocuSign | 3 requests/month | 25 MB | Browser, iOS, Android | Yes | Yes |
| Smallpdf eSign | 2 docs/day | 5 GB | Browser | Optional | Yes |
| PDF24 Tools | Unlimited | Unlimited | Browser + Desktop (Windows) | No | Yes |
| ILovePDF Sign | Unlimited (basic) | 1 GB | Browser | No | Yes |
Signing PDFs used to mean printing, scribbling your name, scanning, and hoping the recipient could read it. That workflow is dead. In 2026, you can sign pdf online in under 90 seconds – for free – without installing anything. I tested eight tools over three weeks for personal and client contracts, and this is the honest breakdown of what actually works.
Before you pick a signing tool, it’s worth knowing whether you need a simple electronic signature (your name drawn or typed on a PDF) or a qualified e-signature with a certificate chain. For most freelance contracts, lease agreements, and business forms in the US and EU, a simple electronic signature is fully legal under ESIGN, UETA, and eIDAS. If you’re dealing with court documents or real estate closings, check local requirements first.
Also worth reading: best free PDF editors – that roundup covers tools for editing PDF content, which pairs well with signing workflows when you need to fill forms before you sign.
1. Adobe Acrobat Online – Free Tier
Adobe invented the PDF format, so it’s no surprise their signing tool handles it cleanly. The free tier lets you sign up to 2 PDFs per month through the browser at acrobat.adobe.com. No desktop install needed, though the desktop app is also available if you’re already in the Adobe ecosystem.
I used it to sign a client services agreement – the signature field placement was accurate, the output file retained all the original formatting, and the download came through immediately. The 2-document monthly cap is the only real friction.
Pricing: Free for 2 PDFs/month. Acrobat Standard starts at $12.99/month. Acrobat Pro is $19.99/month.
File size limit: Up to 2 GB per file on free tier.
Platforms: Browser (Chrome, Firefox, Edge, Safari), Windows desktop, macOS desktop, iOS, Android.
Best for: Occasional signers who want the most polished, trusted interface.
- ✅ Trusted globally by enterprises and governments
- ✅ Handles complex PDF forms without breaking layout
- ✅ 2 GB file size limit – generous for free
- ✅ Certificate-based signatures available on paid plans
- ❌ Only 2 documents/month free – hits the wall fast
- ❌ Requires Adobe account
- ❌ Can feel heavy if all you need is a quick signature
2. DocuSign – Industry Standard
If you’ve ever received a contract from a large company, it probably came through DocuSign. The free plan gives you 3 signature requests per month – meaning you can send documents to others for their signature, not just sign things yourself. That’s a meaningful distinction.
The interface is the most polished of any tool here. Drag-and-drop field placement, automatic email reminders to signers, and an audit trail that shows who signed what and when. Legally binding in 188 countries. For anyone doing occasional client work, 3 requests/month is actually enough if you’re not burning through contracts every week.
Pricing: Free plan: 3 signature requests/month. Personal plan: $15/month. Standard plan: $45/month/user.
File size limit: 25 MB per document on free plan.
Platforms: Browser, iOS, Android.
Best for: Freelancers and small businesses who send contracts to clients and need signatures back.
- ✅ Audit trail with timestamps and IP addresses
- ✅ Send to multiple signers in sequence
- ✅ Mobile apps are genuinely good
- ✅ Recognized and accepted everywhere
- ❌ 25 MB file limit is tight for design portfolios or scan-heavy docs
- ❌ Free plan is 3 outbound requests, not unlimited self-signing
- ❌ Overkill if you just need to sign something yourself
3. Smallpdf eSign
Smallpdf started as a PDF compression tool and has grown into a decent all-in-one PDF suite. Their eSign feature lets you sign 2 documents per day without an account – you just drag the file in, place your signature, and download. The daily limit resets at midnight UTC.
Honestly, the no-account option is what makes it stand out. For one-off signatures on documents from people who don’t know you’re signing online, it’s frictionless. The signature itself can be drawn, typed, or uploaded as an image.
If you’re also compressing large PDFs before sending, check out how to compress PDF files online free – Smallpdf shows up there too.
Pricing: Free: 2 docs/day. Smallpdf Pro: $12/month (annual) or $18/month.
File size limit: Up to 5 GB with an account; 1 GB without.
Platforms: Browser only (no desktop app).
Best for: Quick, occasional signing without creating another account.
- ✅ No account required for basic signing
- ✅ Clean, fast interface – sign in under 2 minutes
- ✅ 5 GB file size limit with account
- ✅ Part of a broader PDF toolkit (compress, merge, convert)
- ❌ 2 documents/day cap hits if you’re processing batches
- ❌ No desktop app – browser only
- ❌ No audit trail on free tier
4. PDF24 Tools – Best Truly Free Option
PDF24 is a German-made tool from Geek Software GmbH, and it’s the most genuinely free option on this list. No document limits, no file size caps, no account required. You can sign unlimited PDFs in the browser or download their free Windows desktop app for offline use.
I ran 23 documents through it in one afternoon testing batch processing scenarios. Not a single one failed. The signing interface is functional rather than beautiful – no fancy drag-to-position signature fields, just upload, add signature, download. For users who prioritize privacy (documents are processed in the browser with optional server-side processing toggle), this is also a strong choice.
The desktop app is Windows-only, which is a real gap if you’re on macOS. But the browser version works on any OS.
Pricing: Completely free. The website has ads. There is a PDF24 Creator desktop app (Windows, free). No paid plans.
File size limit: No stated limit. Practical limit depends on browser memory – files above 500 MB can be slow.
Platforms: Browser (all OS), Windows desktop.
Best for: High-volume signers, privacy-conscious users, anyone who hates hitting free tier limits.
- ✅ Truly unlimited – no caps on documents or file size
- ✅ No account required
- ✅ Desktop app available for Windows (offline use)
- ✅ Optional local processing mode for sensitive documents
- ✅ 40+ other PDF tools available in the same interface
- ❌ Interface is dated compared to DocuSign or Adobe
- ❌ Desktop app is Windows-only
- ❌ No audit trail or signer tracking
- ❌ Ads on the website
5. SignNow
SignNow sits between DocuSign and the simpler browser tools. The free trial runs 7 days with full access, after which it drops to $8/month per user on the Business plan (annual billing). That’s one of the cheaper paid options in the e-signature space.
What sets SignNow apart is its template system – if you’re signing the same type of contract repeatedly, you set the signature fields once and reuse the template. The mobile apps (iOS and Android) are well-built and let you sign in the field without pulling out a laptop. I tested the iOS app for signing rental agreements at a property visit – worked smoothly on a 4G connection.
Pricing: 7-day free trial (no credit card required). Business: $8/user/month (annual) or $20/month. Business Premium: $15/user/month (annual).
File size limit: 25 MB per document.
Platforms: Browser, iOS, Android.
Best for: Small teams who sign contracts regularly and need templates and mobile access.
- ✅ Reusable templates save time on recurring document types
- ✅ Strong mobile apps
- ✅ Cheapest paid plan at $8/month
- ✅ Bulk send to multiple signers
- ❌ No permanent free tier – only 7-day trial
- ❌ 25 MB file limit
- ❌ Some advanced features locked behind Business Premium
6. HelloSign (Dropbox Sign)
HelloSign was rebranded as Dropbox Sign in 2022 after Dropbox acquired it. The free plan allows 3 signature requests per month – same as DocuSign’s free tier, but with tighter Dropbox integration if you already use Dropbox for file storage.
The interface is clean and slightly more streamlined than DocuSign. If your workflow involves storing signed documents directly in Dropbox folders (auto-save after signing), this saves a manual step. The API is also available for developers on paid plans.
Pricing: Free: 3 signature requests/month. Essentials: $15/month. Standard: $25/user/month.
File size limit: 40 MB per document.
Platforms: Browser, iOS, Android, Dropbox integration.
Best for: Existing Dropbox users who want native signing without switching ecosystems.
- ✅ 40 MB file size limit – more generous than DocuSign’s 25 MB
- ✅ Direct Dropbox integration for auto-save
- ✅ Clean, easy interface
- ✅ Audit trail on all plans
- ❌ Only 3 outbound requests/month free
- ❌ Less brand recognition than DocuSign (some clients flag unfamiliar platforms)
- ❌ Loses appeal if you’re not already in the Dropbox ecosystem
7. ILovePDF Sign
ILovePDF is a Barcelona-based tool that’s been expanding from its original PDF utility focus into signing. The signing feature is free, browser-based, and doesn’t require an account for basic use. File size limit is 1 GB per document.
The interface is simple enough that my non-technical colleagues could figure it out without a tutorial. You upload, add a signature (draw, type, or image upload), position it, and download. No email verification, no waiting for confirmation links.
Pricing: Free (unlimited basic signing). ILovePDF Premium: $7/month (annual) or $14/month for additional features.
File size limit: 1 GB per file.
Platforms: Browser, iOS, Android.
Best for: Simple one-off signatures with no account setup.
- ✅ Free with no document limits for basic signing
- ✅ No account required
- ✅ 1 GB file size limit
- ✅ Also handles compression, merging, conversion
- ❌ No audit trail on free tier
- ❌ Less feature-rich than DocuSign for sending to others
- ❌ UI is basic – fine for simple use, limiting for complex forms
8. macOS Preview and Windows Built-In Tools
Look – the best tool is sometimes already on your computer. macOS Preview has had a built-in signature feature since OS X Mountain Lion (2012). You can draw your signature on a trackpad, capture it with the camera, or type it, then place it on any PDF. No internet connection. No file size limits. No accounts.
Windows is a bit more fragmented. Windows 11 includes Microsoft Edge, which can annotate PDFs, and the built-in Photos app can handle basic markup. The Microsoft 365 apps (Word, etc.) can sign PDFs if you have a subscription. For truly free Windows PDF signing without third-party tools, the options are thinner than on macOS.
Pricing: Free – already included in the OS.
File size limit: Limited by available RAM. Practically handles files up to several hundred MB without issues.
Platforms: macOS (Preview), Windows 11 (Edge PDF viewer for basic annotation).
Best for: macOS users who want offline signing with zero setup. Windows users who need a quick annotation rather than a formal signature workflow.
- ✅ Already installed – zero setup
- ✅ Fully offline – no data uploaded anywhere
- ✅ No document limits
- ✅ macOS Preview signature is surprisingly good quality
- ❌ No audit trail – no proof of who signed or when
- ❌ Windows built-in options are weaker than macOS Preview
- ❌ Can’t send to others for signature – self-signing only
- ❌ Not recognized as “formally signed” by some legal requirements
Which Tool Should You Actually Use
Here’s how I’d break it down based on what you’re actually trying to do:
You sign a few documents per month and want something free forever: PDF24 or ILovePDF. No caps, no accounts, just sign and download.
You need to send contracts to clients and get signatures back: DocuSign free tier (3 requests/month) or HelloSign (3 requests/month). DocuSign has wider recognition. If you need more than 3/month, SignNow at $8/month is the most cost-effective paid option.
You’re on macOS and only need to sign things yourself: Preview. Seriously, don’t install anything else.
You process high volumes or handle sensitive documents: PDF24 with local processing mode, or invest in Adobe Acrobat Pro at $19.99/month for the full certificate-based signing workflow.
For teams that also need to merge multiple signed documents, how to combine PDF files free covers the merging tools that play well with these signing workflows.
A Note on Legal Validity
Every tool on this list produces signatures that are legally binding in most jurisdictions for standard business contracts. The ESIGN Act (US, 2000) and eIDAS (EU, 2016) both recognize electronic signatures as valid. The practical difference between tools isn’t about legal validity – it’s about audit trails and verifiability. If a dispute arises, DocuSign’s timestamped audit trail is easier to present as evidence than a signature added in macOS Preview.
For high-stakes documents – court filings, real estate deeds, notarized documents – consult a local attorney before relying on any of these tools.
Frequently Asked Questions
Is signing a PDF online actually free?
Yes, with real caveats. PDF24 and ILovePDF offer genuinely unlimited free signing. Adobe Acrobat, DocuSign, and HelloSign cap free use at 2-3 documents per month, which covers occasional use but not regular business volume. If you hit those caps, PDF24 is the obvious free alternative – no limits, no account, no cost. Full breakdown of the free PDF editing landscape is at best free PDF editors.
Are online PDF signatures legally binding?
In most cases, yes. The US ESIGN Act (2000) and EU eIDAS regulation (2016) both recognize electronic signatures as legally equivalent to handwritten signatures for most contract types. The exceptions include wills, adoption papers, some court documents, and real estate closings in certain states – these still require wet (ink) signatures or notarization. When in doubt, check your jurisdiction’s specific requirements.
What’s the difference between an electronic signature and a digital signature?
An electronic signature is any electronic mark indicating agreement – a typed name, a drawn signature, a clicked “I agree.” A digital signature is a technical mechanism using public-key cryptography: it creates a unique mathematical fingerprint tied to a certificate issued to a specific person. Adobe Acrobat Pro and DocuSign’s higher tiers support digital signatures with certificate chains. For most business contracts, a standard electronic signature is sufficient. Digital signatures matter when the document needs to be provably tamper-evident and tied to a specific verified identity.
Can I sign a PDF on my phone for free?
Yes. DocuSign, SignNow, HelloSign, and ILovePDF all have free mobile apps for iOS and Android. DocuSign’s free tier lets you sign documents sent to you without any limit – the 3/month cap only applies to documents you send to others. For self-signing on mobile, Adobe Acrobat’s free iOS and Android app also works (within the 2/month cap). Not gonna lie – the DocuSign mobile app is the smoothest experience of the ones I tested.