If you live in Google Workspace, your first instinct when someone sends you a PDF to sign is probably to open it in Google Docs. But Google Docs has a fundamental limitation that many users discover only when they need it most: it cannot sign existing PDF files. Understanding why — and knowing the best alternatives — will save you a lot of frustration.
Why Google Docs cannot sign PDFs
Google Docs is a word processor. It can create documents, export them to PDF, and even open simple PDFs by converting them to editable Google Docs format. But that conversion process destroys the original PDF's formatting, and it has no concept of a signature field or an e-signature workflow.
When you upload an existing PDF to Google Drive and open it, you can view it and add limited annotations using the Markup tool. But the Markup tool is a basic drawing layer — you can draw a freehand squiggle over a document, but this is not a legally coherent signature experience and the output is not a proper signed PDF with embedded signature metadata.
Google has not added proper PDF signing to Google Docs or Google Drive as of 2026. For users who need to sign PDFs as part of a Google Workspace workflow, the options are either third-party browser tools or Google Workspace add-ons.
The four best alternatives, compared
| Tool | Works in browser | Free tier | Watermark-free | Encrypted storage | No account needed |
|---|---|---|---|---|---|
| PrimeDocu | Yes | Yes — unlimited | Yes | Yes (AES-256-GCM) | Free account (no card) |
| Google Drive Markup | Yes | Yes | Yes | No (Google standard) | Requires Google account |
| Smallpdf | Yes | 2 tasks/day only | No (free tier) | No | No account for basic use |
| DocuSign (Workspace add-on) | Yes (via add-on) | 3 sends/month | Yes | Yes (SOC 2) | No — account required |
Option 1 — PrimeDocu (recommended for Google Workspace users)
PrimeDocu works in Chrome exactly like Google Docs — open your browser, go to primedocu.com, upload your PDF, and sign a PDF online. No extension install required. The signed PDF is stored in your encrypted vault and downloadable immediately. The free plan includes unlimited PDF signing with no watermarks and no credit card. For Google Workspace users who want a consistent, browser-based experience, this is the closest equivalent to using a Google product.
Option 2 — Google Drive Markup
If you need something that never leaves the Google ecosystem: open the PDF in Google Drive, click the pencil icon to open Markup mode, and draw your signature freehand. This is passable for informal documents — scan of a handwritten letter, a quick approval — but produces a drawing overlay rather than an embedded PDF signature. There is no signature date stamp, no audit trail, and no way to add a typed or generated signature — the practical difference between an electronic signature and a digital signature matters here. Not suitable for contracts.
Option 3 — Smallpdf
Smallpdf's Sign PDF tool is clean and easy to use. The free tier allows two tasks per day, which may be sufficient for occasional use. However, free-tier signed PDFs include a Smallpdf watermark, and documents are processed on Smallpdf's servers rather than your device. For regular business use or sensitive documents, the watermark and server-side processing are drawbacks.
Option 4 — DocuSign Google Workspace Add-on
DocuSign integrates directly into Gmail and Google Drive, making it the most workflow-native option for enterprise teams. The free tier allows three envelope sends per month. Beyond that, plans start at around £10/month per user. DocuSign is the industry standard for high-stakes contracts requiring an audit trail and multi-party workflow, but it is significantly over-engineered (and over-priced) for everyday document signing.
Which should you choose?
For individuals and small businesses signing PDFs in the browser: PrimeDocu. Free, no watermarks, no credit card, works in Chrome, and stores signed documents in an encrypted vault — not a general-purpose cloud drive.
For enterprise teams requiring multi-party workflows, audit certificates, and deep Google Workspace integration: DocuSign.
For one-off documents where you are already in Google Drive and just need to mark something quickly: Google Drive Markup — with the understanding that it is not a proper e-signature tool.
Frequently asked questions
Can Google Docs sign PDFs?
No. Google Docs can open and edit Word documents and export to PDF, but it cannot open, annotate, or sign an existing PDF file in any meaningful way. Google Drive's Markup tool lets you draw on a PDF, but this is not a proper e-signature workflow. For signing existing PDFs, you need a dedicated tool like PrimeDocu.
What is the best Google Docs alternative for PDF signing?
PrimeDocu is the closest like-for-like alternative: browser-based, free to start, no credit card, no watermarks, and encrypted storage. For enterprise teams needing multi-party workflows and audit certificates, DocuSign is the industry standard at a higher price.
Is there a free PDF signer that works in the browser like Google Docs?
Yes — PrimeDocu works entirely in the browser with no install required. Upload your PDF, draw or type your signature, position it, and download the signed file — all within a Chrome tab. The free plan includes unlimited signing with no watermarks.
Is a PDF signed with a free tool legally binding?
Yes, for the vast majority of everyday contracts. Electronic signatures are legally binding under the Electronic Communications Act 2000 (UK), eIDAS (EU), and ESIGN/UETA (US) regardless of the software used. The legal requirement is intent to sign, not the sophistication of the tool. Only a narrow category of documents — land transfers, wills — require more formal signing processes.