TL;DR: Upload a PDF, draw or type your signature, place it on any page, and download the signed PDF.
Add signature to PDF online for free. Draw, type, or upload your signature image and place it anywhere on the document. Create legally-binding electronic signatures without printing. No account required.
Sign PDF runs on the same privacy-first stack as every PrivaTools utility: files enter an isolated Docker container, use temporary per-request storage, and are unlinked the moment your download begins. No account, no watermark, no daily quota.
Add signature to PDF online for free. Draw, type, or upload your signature image and place it anywhere on the document. Create legally-binding electronic signatures without printing. No account required. Use it when you need a quick, private, no-account way to handle a pdf in the browser, or when you want an auditable open-source alternative to iLovePDF, Smallpdf, Adobe Acrobat, PDF24, and Sejda. The page at /tool/sign-pdf is designed for one clear job: upload or provide the input, choose only the options that matter, and download the result without creating an account or passing through a sales funnel.
PDF operations that need server-side libraries run inside the PrivaTools container and return a fresh download; browser-only PDF helpers stay on-device. Temporary input and output files are not used for analytics, model training, advertising profiles, or product telemetry. The public demo uses anonymous page-view analytics only; file bytes, extracted text, filenames, passwords, signatures, and generated results are outside that analytics path. If your organization needs stricter controls, you can self-host all 214 PrivaTools utilities and keep processing on your own infrastructure.
Before running Sign PDF, confirm that the source file opens correctly and that you have permission to process it. Keep an untouched original, run one operation at a time when quality matters, and use Pipeline when you want repeatable multi-step output. For sensitive material, review the downloaded result before sharing it. For large files, give the browser time to finish the download and avoid refreshing the page mid-run. If a password, damaged upload, unsupported codec, or malformed document blocks processing, PrivaTools returns a plain-language error so you can pick the next recovery step instead of guessing.
Sign PDF is intentionally narrow: it does one pdf task and hands the result back as a normal download. That makes the output easy to inspect, rename, archive, attach to email, or feed into another tool. If you need a repeatable workflow, save the page, bookmark a Pipeline recipe, or self-host the API so the same steps can run from internal scripts. The interface avoids accounts and cloud folders on purpose: the safest default for private files is to process only the current request, return the result, and leave long-term storage under your control.
Sign PDF runs in any modern browser on Windows, macOS, Linux, Android, and iOS — there is nothing to install, no extension to add, and no desktop app to keep updated. Because the interface is a single page, you can bookmark it, send the link to a colleague, or open it on a phone and get the same result you would on a laptop. There are no watermarks stamped onto your output, no sign-in wall before the download, and no paid tier that unlocks the “real” version later — the Sign PDF you see is the complete tool. For teams that would rather keep everything in-house, the same endpoint ships in the MIT-licensed, self-hostable build, so you can run it behind your own firewall with identical behaviour and no outbound calls. That combination — instant in the browser for individuals, fully self-hostable for organizations — is what keeps a private file genuinely private from upload to download.
PrivaTools creates a visual signature embedded in the PDF, plus an audit trail in the document metadata (signer name, timestamp). Whether it qualifies as legally binding depends on your jurisdiction — for most informal agreements, internal sign-offs, and consent forms in the US, EU, UK, India, and Australia, it is widely accepted under ESIGN and eIDAS frameworks. For court-grade qualified signatures, you need a certified eID provider.
Yes. After creating your signature, you can place it on any page by navigating through the document preview. Add as many signatures as needed (e.g. initial-each-page or multi-party contracts).
No. Your signature exists only in your browser session — drawn on a canvas, kept in memory while you place it. The server receives the signature image only for the brief moment it embeds it into the PDF, then unlinks both input and output within seconds of your download. The signature image is never kept after the response.
Yes. The PDF and signature image are held in temporary per-request storage inside an isolated Docker container for the duration of the request only; both are unlinked the moment your download begins. Nothing is logged, indexed, or sent to a third-party API. The signing pipeline is open source on GitHub and you can self-host the entire stack.
500 MB per file with no daily or monthly quota. There is no cap on the number of signatures you can place.
No — no account, no email, no sign-up. Upload, draw, place, download. DocuSign and Adobe Sign both require accounts; we don't.
Free with no daily limit and no account required. PrivaTools handles single-signer documents extremely well; for multi-party serial signing with email reminders and a portal-style workflow, DocuSign or Adobe Sign remain more featureful. We don't retain the file or have access to it after delivery.
See how PrivaTools compares to iLovePDF, Smallpdf, Adobe Acrobat, and other free PDF tools.