HelperCrateSign PDF
Place a signature image from the generator or your device on any PDF page.
Your files never leave your device. Everything runs in your browser.
What Sign PDF does
Sign PDF places a signature image — created in the Signature Generator or uploaded as a PNG — onto one or more pages of a PDF, then saves a signed copy.
The result is a visual signature, like signing a printed page with a pen: an image drawn over the document. It is not a cryptographic digital signature and carries no certificate, so it cannot prove who signed or detect later changes to the file. Plenty of everyday situations only need the visual kind — forms, letters, internal approvals.
The workflow is two steps: get a signature, then place it. Signatures made or uploaded are kept on this device, and the PDF never leaves the browser.
How to use Sign PDF
- In step 1, either click Create a signature (the generator hands the result straight back), pick a saved signature thumbnail, or upload a PNG with Upload PNG.
- In step 2, drop the PDF onto the dropzone.
- Click a page thumbnail to place the signature near the top-left of that page.
- Drag the placed signature to the right spot, and click further pages to add more placements if several pages need signing.
- Click Download signed PDF; the file saves with a -signed suffix.
Features
- Three signature sources: the built-in generator, previously saved signatures on this device, or a PNG upload.
- Thumbnail view of every page; click to place, drag to position, with multiple placements supported.
- The signature keeps its proportions and scales with the page, so what you see on the thumbnail matches the output.
- Saved signatures live in on-device storage (IndexedDB with a local-storage fallback), capped at 10.
- Output is a new PDF written with pdf-lib; the original document is untouched.
- Works with any page size — placements are converted from thumbnail scale to PDF points when saving.
Tips and common mistakes
- Generate the signature with the name you actually sign, so saved signatures stay easy to tell apart.
- Place the signature just above a printed name line so both remain visible.
- For documents with several signatories, give each person a different ink colour in the generator before placing the signatures.
Frequently asked questions
Is this a legally binding electronic signature?
This tool produces a visual signature only: an image placed on the page. It has no certificate and cannot prove the signer's identity or detect later edits. If a situation calls for a qualified or certified e-signature — or you need advice about legal validity — use a dedicated e-signature service or ask a professional.
Which image formats can I upload?
PNG is the format the tool embeds. The picker also lists JPEG, but the embedding path is PNG-only in this version, so export a JPEG to PNG first — the Image Converter does that in one step.
Where are my saved signatures stored?
On this device only: IndexedDB where available, with a local-storage fallback, keeping up to 10 signatures. Nothing is uploaded, and clearing the browser's site data removes them.
Can I sign several pages at once?
Yes. Click each page thumbnail to add a placement, drag each one into position, and all placements are drawn when you save.
Can I resize the signature?
The on-screen width is fixed so placement stays predictable. To change proportions, generate the signature with different sliders in the Signature Generator, or prepare a wider or tighter PNG.
What if the PDF already has a digital signature?
Adding a visual signature re-saves the file, which invalidates any existing cryptographic signature on it. Only sign documents whose digital signatures you no longer need to keep valid.
Related pdf tools: Signature Generator, PDF Watermark, PDF Metadata Editor.
Signatures are created, stored and placed on your device; neither the PDF nor the signature image is uploaded.