How to overlay an approved stamp onto a pdf
- Step 1Design the APPROVED mark as a full-page transparent PDF — In your design tool, create a page the same size as the document, place the APPROVED graphic exactly where you want it on the page (e.g. top-right corner or diagonally over the body), keep the rest of the page transparent, and export a single-page PDF. If your approval mark is a PNG/JPEG, convert it via image-to-pdf first — only PDFs are accepted as stamps.
- Step 2Open the Stamp tool — Go to PDF Overlay / Stamp. The dropzone accepts multiple PDFs because this tool combines two files.
- Step 3Add the document first, the stamp second — Drop the document to be approved first, then the APPROVED stamp PDF second. The first file is the base, the second is the overlay — the queue lists both so you can verify the order.
- Step 4Process the two files — Click Process 2 files. The stamp's first page is centred, fit-scaled, and drawn at 50% opacity on every page. No further settings.
- Step 5Verify the mark reads clearly — Open the result. At 50% opacity an APPROVED mark should still be legible against the page; if it looks faint, make the artwork bolder/darker and re-stamp, since opacity isn't adjustable here.
- Step 6Download and file — Save
yourdoc.stamp.pdfto your records system. If approvals must not be removed, flatten the file before distributing.
Approval-stamp behaviour vs what people expect
Desktop stamp apps offer corner placement and per-page targeting; this tool does not. Plan around the fixed behaviour.
| You might expect | What this tool actually does |
|---|---|
| Drop a small APPROVED image in a corner | Only PDFs accepted; the stamp is centred, not corner-placed. A small graphic lands mid-page |
| Stamp only page 1 (the signature page) | Applied to every page — no page selector |
| Set the stamp's size on the page | Auto fit-to-page, scaled down only (never enlarged) |
| Adjust how opaque the stamp is | Fixed 50% opacity — bake darkness into the artwork |
| Place a stamp behind the text | Drawn on top of the content |
How to get the APPROVED mark where you want it
Since position is always centre, you position by where you draw the mark on a full-page transparent stamp PDF.
| Desired placement | Design the stamp PDF as… |
|---|---|
| Top-right corner | Full-page transparent PDF with the APPROVED graphic in the top-right; rest transparent |
| Diagonal across the page | Full-page transparent PDF with a large rotated APPROVED banner over the centre |
| Footer / sign-off band | Full-page transparent PDF with the mark + date line near the bottom edge |
| Small centred seal | Full-page transparent PDF with the seal in the centre (this is the only placement that works with a non-full-page stamp) |
Free vs Pro limits (PDF tools)
Per-file limits — both the document and the stamp count separately.
| Limit | Free | Pro |
|---|---|---|
| Max file size (per PDF) | 2 MB | 50 MB |
| Page limit (per PDF) | 50 pages | 500 pages |
| Files combined per run | Base + stamp | Base + stamp |
Cookbook
Approval-workflow recipes that work with the centred, fixed-opacity, every-page overlay.
Diagonal APPROVED banner across a contract
You want a bold diagonal APPROVED stamp visible on every page of a signed contract.
stamp PDF: approved-diagonal.pdf (full A4 page, large rotated 'APPROVED' banner over the centre, rest transparent) base: contract.pdf (8 pages) Process 2 files → banner centred + fit-to-page at 50% opacity on all 8 pages Output: contract.stamp.pdf
Top-right APPROVED seal
A small seal in the top-right of each page. Because the tool centres, you place the seal at top-right on a full-page transparent stamp.
WRONG: seal-only.pdf (a 120x120 pt seal) → centred → lands in the middle of the page RIGHT: seal-topright.pdf (full A4 page, seal drawn at top-right, rest transparent) → centred full page → seal appears top-right
APPROVED mark from a PNG
HR sent the approval mark as a transparent PNG. Convert before stamping.
image-to-pdf: approved.png → approved.pdf (single page) pdf-stamp: base: change-order.pdf stamp: approved.pdf → change-order.stamp.pdf
Mark looks too faint
A light-grey APPROVED mark disappears at 50% opacity.
Symptom: 'APPROVED' barely visible on the page
Cause: 50% opacity halves the mark's strength,
and there's no opacity control to raise it.
Fix: re-author the mark in a strong colour
(e.g. solid red) so 50% still reads clearly,
then re-stamp.Lock the approval so it can't be edited out
After stamping, flatten the document so the mark is baked in.
1. pdf-stamp: doc.pdf + approved.pdf → doc.stamp.pdf 2. pdf-flatten: doc.stamp.pdf → flattened, single-layer PDF (Note: a visual stamp is a convenience mark, not a cryptographic approval — see the FAQ.)
Edge cases and what actually happens
Small APPROVED graphic lands in the page centre
By designThe tool centres the stamp. A small corner-sized graphic therefore appears mid-page, not in a corner. To get a corner placement, draw the mark in the corner of a full-page transparent stamp PDF; centring the full page then positions the mark correctly.
Approval mark supplied as PNG/JPEG
invalid inputOnly PDFs are accepted as the stamp. Convert the approval image to a single-page PDF with image-to-pdf, then use that as the stamp.
You only wanted page 1 (the signature page) stamped
By designThe overlay is applied to every page; there is no page selector. For most approval marks an every-page stamp is acceptable. If a single page is essential, isolate it, stamp it, and merge it back with pdf-merge.
APPROVED mark too faint at 50% opacity
design issueOpacity is fixed at 50% with no control. A pale mark loses too much strength. Author the mark in a strong, saturated colour (classic stamp red works well) so the half-opacity draw still reads clearly.
Only one file uploaded
errorTwo files are required ("Upload a base PDF and a stamp PDF."). The Process button stays disabled until both the document and the stamp PDF are in the queue.
Stamp PDF has more than one page
first page usedOnly the first page of the stamp PDF is used and repeated on every base page; extra pages are ignored. Keep the approval stamp a single-page PDF.
User added stamp before the document
order mattersThe first queued PDF is the base and the second is the stamp. If you added the stamp first, your roles are swapped — remove and re-add in document-then-stamp order using the queue's remove (×) control.
Is this a legally binding approval?
Not legal proofA drawn/overlaid stamp is a visual convenience mark, not cryptographic proof of who approved or when. For verifiable sign-off use a digital signature and verify it with pdf-signature-verify.
Output file noticeably larger
ExpectedDrawing the stamp on every page adds content to each page. If the size matters, losslessly compress the stamped result.
Free tier exceeded (over 2 MB / 50 pages)
tier limitFree tier caps each PDF at 2 MB and 50 pages; Pro raises this to 50 MB and 500 pages. Compress or split a large document, or upgrade.
Frequently asked questions
Can I place the APPROVED stamp in the top-right corner?
Not via a position setting — the tool always centres the stamp. To get a corner placement, design a full-page transparent stamp PDF with the APPROVED graphic drawn in the top-right corner and the rest of the page transparent. When the full page is centred over the document, the mark lands in the top-right exactly as you drew it.
Can I stamp APPROVED on just the signature page?
No — the overlay is applied to every page and there is no page-range option. For most approval marks, an every-page stamp is fine and arguably clearer. If a single page is truly required, extract that page, stamp it, and merge it back with pdf-merge.
My APPROVED image is a PNG — can I use it?
Only as a PDF. Convert the PNG to a single-page PDF with image-to-pdf first, ideally drawn at the document's page size with the mark positioned where you want it, then use that PDF as the stamp.
Why does my APPROVED mark look faded?
The stamp is drawn at a fixed 50% opacity and there's no control to change it. A light-coloured mark fades too much. Re-author it in a strong, saturated colour (solid red is the traditional choice) so it stays legible at half opacity, then stamp again.
Can I add a date to the APPROVED stamp?
Bake the date into your stamp PDF artwork before uploading — the tool draws the stamp exactly as designed and has no text-input field. For a separate date/text overlay you could combine this with page numbers or design the date directly into the approval graphic.
Will this create a legally binding approval?
No. A visual stamp is a convenience marker, not cryptographic proof. For a legally meaningful sign-off, use a digital signature and verify it with pdf-signature-verify. The stamp tool only paints a graphic onto the page.
Can I stop someone removing the stamp afterwards?
Stamping draws the mark onto the page content, but a sophisticated editor could still alter it. To make tampering harder, run the stamped file through pdf-flatten so the layers are merged. For true integrity, a digital signature is the right mechanism.
Does the order of the two files matter?
Yes. The first PDF you add is the base document; the second is the APPROVED stamp. Add the document first, then the stamp. The file queue shows both with page counts so you can confirm before processing.
Is my document uploaded anywhere?
No. Both the document and the stamp are processed entirely in your browser. Approval-workflow files — contracts, POs, change orders — never leave your device; only an anonymous usage counter is logged when signed in.
How many pages / how large a file can I stamp?
Free tier allows up to 2 MB and 50 pages per PDF; Pro raises this to 50 MB and 500 pages. The limits apply to the document and the stamp independently.
What output do I get?
A standard PDF named yourdoc.stamp.pdf with the approval mark overlaid on every page. It opens in any reader and can be filed in your DMS. If embedding the stamp grew the file, compress it losslessly before distribution.
What's the difference between this and the watermark tool?
The watermark tool types diagonal text with adjustable opacity and font size (e.g. a "DRAFT" watermark). The Stamp tool overlays a designed PDF page centred at fixed 50% opacity. For a text APPROVED mark with opacity control, watermark may suit better; for a graphical seal, use stamp.
Privacy first
All PDF processing runs locally in your browser using PDF-lib and pdf.js. No file is ever uploaded — only metadata counters are saved for signed-in dashboard stats.