Digital Stamp Maker
A stamp maker draws the face. What almost none of them do is tell you whether the file you just downloaded actually fits where you are about to put it — a Word paragraph, a Google Doc, a PDF signature line, an email footer, where placement size and display settings vary. Build the stamp below, then size it for the one place it is actually going.
Digital stamp maker: draw it, then size it
PNG, JPG or SVG, up to 5MB. Tinted to match the ink color below and replaces the center text — 100% on-device, never uploaded.
Free exports add a small “stampmakertool.com” line under the stamp — never over it — and cap at 1000px.
Batch export — generate multiple stamps at oncePRO
One name per line (uses the top-text field; everything else — shape, ink, logo — stays as set above). Up to 40 rows, downloaded as a single zip of PNGs.
Want a physical stamp?
StampMakerTool only makes digital designs — we don't sell or ship physical stamps, and we're not partnered with anyone who does.
Download the highest-resolution file you have access to (SVG is best if the shop asks for vector art) and take it to a local rubber-stamp, engraving, or notary-supply shop — most accept a PNG or SVG upload directly and can quote you on the spot.
Set the size and resolution preset below before downloading the PNG. Its square canvas uses the calculated width (303px); rectangular height recommendations do not reshape the artwork. Widths above your plan limit are refused, not silently reduced. SVG stays scalable. Set the physical placement size in your document.
This is how big the stamp should look once it is placed — not the size of any physical rubber plate. 35mm is about 1.38″.
35mm at 220 dpi for word: office 220 ppi compression preset: 35 ÷ 25.4 × 220 ≈ 303px wide.
| Target | Target ppi | Export size at 35mm | Best for | Not for |
|---|---|---|---|---|
| Word: Office 220 ppi compression preset | 220 | 303×303px | A stamp on a letter, invoice or form that may get printed | A logo shown only inside a Teams call or a shared screen |
| Google Docs: our 150 ppi estimate | 150 | 207×207px | A stamp on a Doc that mostly gets read on screen and shared by link | A Doc you plan to print at full page width and hand out physically |
| PDF: 300 ppi print convention | 300 | 413×413px | A signature or seal on a PDF that may be printed, scanned or archived | A PDF that will only ever be viewed on a phone and never printed |
| Email: Office 96 ppi compression preset | 96 | 132×132px | A small logo or seal sitting under your name in every email you send | Anything that will be printed later — an email image rarely is |
| Print: 300 ppi convention | 300 | 413×413px | Anything headed to an actual printer rather than a screen | A file that never leaves a screen |
Your dimensions, file contents and file metadata stay in this tab. The checker reads pixels locally. Usage events record actions and preset selections, without file details.
Which target should you export for?
These presets offer starting points for sizing. The 96, 150 and 220 ppi values are Office picture compression options, not requirements for email, Google Docs or Word. Assigning 150 ppi to Google Docs is our inference. The 300 ppi presets use a print convention, including for PDFs you intend to print.
- Word: Office 220 ppi compression preset (220 ppi target) — Office offers 220 ppi as a picture compression option. We use it as a Word sizing preset, not a minimum that Word requires.
- Google Docs: our 150 ppi estimate (150 ppi target) — We choose 150 ppi for this screen-oriented preset, borrowing an Office compression option. This is our inference, not Google Docs guidance or a rendering requirement.
- PDF: 300 ppi print convention (300 ppi target) — We apply Printivity's 300 ppi print convention to PDFs intended for print. PDF itself does not require this resolution.
- Email: Office 96 ppi compression preset (96 ppi target) — Office offers a 96 ppi email compression option. We use it as a compact starting point, not a requirement of email clients; high-density screens may benefit from more pixels.
- Print: 300 ppi convention (300 ppi target) — Printivity recommends 300 ppi for print images. Confirm the resolution and physical size with your printer.
Four real jobs, worked out
The pixel math a digital stamp maker should show you
Image resolution is pixels divided by the physical width:ppi = pixels / inches. To choose a pixel count, use pixels = (mm / 25.4) × target ppi and round to a whole pixel. One inch is exactly 25.4mm; the preset resolution is a choice, and the resulting effective resolution is approximate.
At 35mm, the 220 ppi preset gives 35 ÷ 25.4 × 220 ≈ 303 pixels across. The 96 ppi preset gives about 132 pixels. More pixels can preserve detail when enlarged or displayed on a high-density screen; fewer may reduce file size. Set the intended physical width after placing the PNG in your document.
The white-box problem
A stamp exported as a plain PNG with no transparency looks fine in the one place it was tested: sitting on a white page in the same tool that made it. Paste it into a dark email theme, a colored footer, or on top of a scanned photo, and the file's rectangular white background shows up as a visible box around the ink. It is the single most common failure in a digital stamp export, and it has nothing to do with the design of the stamp itself — it is entirely a property of how the file was saved.
The checker samples the edges and probes the interior for obvious contradictions. Fully transparent sampled edges do not prove that the inside is transparent. Partial alpha means colour can still show; opaque edges may be an outline or a fill. Conflicting samples return an unclear result. Preview on a contrasting page before deciding whether to re-export.
What this digital stamp maker can't tell you
The size calculator uses chosen resolution presets, not a measurement of your specific document. Word, Google Docs and the PDF readers people use all have their own scaling quirks, and a file at the rounded pixel count this page calculates can still be resized smaller or larger once it is placed — at which point the effective resolution changes again, and this page has no way to see that it happened.
The transparency checker reads pixels, not intent. It can tell you that a border is opaque and pale; it cannot tell you that you meant it that way, or that the rest of the stamp inside that border is correct. The checker accepts static PNG only, up to 20 MiB and 30 megapixels. It checks the header before decoding and verifies decoded dimensions again before allocating a canvas.
It is not print advice, either. Whether your specific printer, copier or PDF workflow needs more or fewer pixels than the figures here is a question for whoever runs that equipment, the same way the rubber-side of this site's size chart defers plate tolerances to the stamp manufacturer rather than guessing at them.
FAQ
What is a digital stamp maker?
Build a stamp face in your browser, choose a physical width and resolution preset, then download its PNG at the calculated width. The PNG uses a square canvas. The checker separately examines sampled edges of an existing static PNG.
What resolution should a digital stamp be for Word or Google Docs?
Our Word preset uses the Office 220 ppi picture compression option. Our Google Docs preset borrows 150 ppi from Office as a screen-oriented estimate; it is not a Google requirement. These are sizing choices, not measurements of how either application renders your file.
Why does my stamp have a white box around it?
An opaque or partly transparent white background can remain visible when placed on a contrasting page. The checker reports sampled edges only. Interior probes can flag contradictions, but cannot prove that the whole background is transparent.
What size should a digital stamp be in pixels?
Choose a physical size and a target resolution. At 35mm, the 300 ppi print preset gives about 413 pixels across; the 96 ppi email preset gives about 132. These are rounded pixel counts, not destination requirements.
Is PNG or SVG better for a digital stamp?
SVG is scalable; PNG has fixed pixel dimensions and is convenient for placing in documents. Either format can contain opaque fills or partial transparency. This checker accepts static PNG only.
Can I use the same file for both email and print?
You can reuse a larger file at a smaller placement size. A smaller export may save bytes, while a larger one may preserve detail on high-density screens and in print. Choose for your workflow; the presets are starting points.
Does DPI matter if I'm never going to print the stamp?
For screens, rendered pixel dimensions and device density matter more than a physical DPI label. The 96 and 150 ppi presets borrow Office compression options for comparison; they do not establish what an email client or Google Docs requires.
Sources: Office compression options (96/150/220 ppi): Microsoft: Office picture compression options. Print convention (300 ppi): Printivity: what resolution should I use for printing. Destination mappings are ours; Google Docs 150 ppi is an inference, not Google guidance.