How to Add a Stamp to a PDF for Free (Without Buying Software)

You don't need Adobe Acrobat Pro. You don't need a $500-a-year subscription. You don't need to download anything heavy or sign up for an account. Adding a stamp to a PDF for free is genuinely simple — and once you've done it once, every future stamp takes about 60 seconds.

The whole workflow has two parts. First, create the stamp itself as a transparent PNG (the part most people skip, then complain about the white box around their stamp). Second, place the PNG on the PDF using free tools you almost certainly already have. This guide covers both halves, with three free placement methods that work for different situations.

When you need to stamp a PDF

A few common situations:

• Marking an invoice as PAID when you've received payment

• Adding a company seal to an outgoing contract or letterhead

• Placing an APPROVED stamp on a document going through internal review

• Adding a "DRAFT" or "CONFIDENTIAL" watermark to in-progress documents

• Marking received documents as RECEIVED with the date for AP processing

• Stamping certificates issued by your business with an official mark

• Adding a logo stamp to outgoing PDFs as a brand element

Different stamps for different uses, but the workflow is the same in every case: create the stamp, place it on the PDF.

Step 1 — Create your stamp as a transparent PNG

This is the half most people get wrong. They scan a paper stamp, try to use a JPG from somewhere on their computer, or take a screenshot from another tool — and end up with a white rectangle around the stamp that looks awful on the finished PDF.

The fix is creating the stamp fresh in a tool that produces a clean transparent PNG by default.

Open the free online stamp maker

Open the free online stamp maker in your browser. No sign-up, no software install, no account creation.

Pick a shape that fits your stamp's purpose

• Round — the most versatile. Works for company seals, workflow stamps (APPROVED, PAID), and general business stamps.

• Rectangular — best for date stamps (RECEIVED ON ___), address stamps, or text-heavy workflow marks.

• Oval — works for company seals when the company name is too long for a comfortable round layout.

• Custom shapes — hexagonal, scalloped, shield, badge — for stamps where the shape itself carries meaning.

Add your text or logo

Type your business name, the stamp text (APPROVED, PAID, RECEIVED), or upload your business logo. For company seals specifically, see the company seal vs company stamp guide for what content to include — formal seals and everyday stamps have different conventions.

Choose color

• Blue — professional, neutral, the most common business stamp color

• Red — high-attention, used for APPROVED, PAID, REJECTED, VOID

• Black — formal, works for any context

• Brand color — matches your business identity

Download as transparent PNG

The default export is transparent PNG. Save the file somewhere you'll find it again — `business-stamp.png` is fine. You'll reuse this same PNG on every future PDF.

That's the stamp created. Now to place it on the PDF.

Step 2A — Insert in Word, export as PDF

This method works for everyone with Microsoft Word installed. It's the simplest free option if you're already a Word user.

The trick: open the PDF in Word

Modern Word versions can open PDFs and convert them to editable Word documents. The conversion isn't always perfect for complex PDFs (formatting can shift), but for stamping purposes — where you're just adding an overlay image — it works well.

Steps

• Open Word. File → Open, then browse to your PDF.

• Word will ask if you want to convert the PDF to an editable Word document. Click OK.

• The PDF appears as a Word document. The text is editable; the layout approximates the original.

• Insert → Pictures → This Device → select your stamp PNG.

• The stamp inserts at your cursor position. Probably too big and probably in the wrong place.

• Right-click the stamp → Wrap Text → In Front of Text. This lets you drag the stamp anywhere on the page without disturbing the document layout.

• Drag the stamp to where you want it. Resize using corner handles only (corner handles preserve proportions; side handles distort the stamp).

• File → Save As → PDF. Save the stamped PDF.

When this method works best

• The PDF doesn't have complex formatting (forms, special tables, embedded fonts)

• You have Word already installed

• You want a quick free option without trying other tools

When this method doesn't work as well

• The PDF has complex formatting that Word's conversion mangles

• You're working with a multi-page PDF and only want to stamp specific pages

• The PDF is locked or password-protected (Word can't convert protected PDFs)

For complex PDFs, Method 2B or 2C is usually a better fit.

Step 2B — Free online PDF tools

For PDFs that Word can't handle cleanly, browser-based PDF tools are the next free option. The two most reliable for stamp insertion:

PDF24

A free browser-based PDF toolset with editing capabilities.

• Go to PDF24's online tools and pick the Edit PDF option.

• Upload your PDF.

• In the editor, click Add Image (or similar Insert Image option).

• Upload your stamp PNG.

• Click on the page where you want the stamp to appear.

• Drag to reposition; use corner handles to resize.

• Click Save or Apply, then download the stamped PDF.

iLovePDF

Similar browser-based PDF toolset.

• Go to iLovePDF and pick the Edit PDF tool.

• Upload your PDF.

• Click Add Image in the toolbar.

• Upload your stamp PNG.

• Position on the page, resize as needed.

• Click Edit PDF to apply changes, download the result.

Privacy note

Both PDF24 and iLovePDF process your files on their servers during your session. For sensitive documents (HR records, legal contracts, anything with personal data of others), be aware that you're uploading the file to a third party. For non-sensitive everyday business documents, this is usually fine.

Free tier limits

Both tools have daily usage limits on the free tier — typically 2-3 tasks per day. For occasional stamp insertion, the free tier is enough. For high-volume stamping, you'd hit the limit quickly.

When this method works best

• The PDF was complex and Word's conversion didn't preserve it cleanly

• You don't have Word installed

• You're working with a one-off PDF that doesn't justify learning new software

Step 2C — Preview on Mac

If you're on a Mac, Preview is built into macOS and handles PDF image insertion natively. No download, no upload, no third-party service.

Steps

• Open the PDF in Preview (double-click it from Finder if Preview is your default PDF viewer).

• Click View → Show Markup Toolbar (or click the markup icon in the top toolbar — it looks like a pen tip).

• Drag your stamp PNG directly from Finder onto the PDF page. Preview embeds it as an image.

• Drag the stamp to position it. Use corner handles to resize.

• File → Save (or File → Export as PDF to make sure the format stays as PDF).

Why Preview is great for stamping

• No upload anywhere — your file never leaves your computer

• Drag-and-drop is faster than menu navigation

• Built into the OS, always available, no installation

• Handles multi-page PDFs naturally — each page is independently stampable

Mac-only limitation

This method only works on macOS. For Windows users, Methods 2A and 2B are the equivalent paths.

Keeping the original clean

A workflow tip that experienced users build into their stamping process: never stamp the original PDF directly. Always make a copy first.

Why

• If you stamp the original and need to send the unstamped version later (for the client's records, for legal proceedings, for a different recipient), you've lost it

• If you stamped the wrong copy (it was a draft, not the final), you have to recreate the original

• For document management and version control, the stamped version is a derivative document — it should have its own filename

Recommended naming convention

For the original: `invoice-INV-001-original.pdf` For the stamped version: `invoice-INV-001-PAID.pdf`

The naming pattern makes it obvious which is which when you look at the folder months later.

When you can stamp the original

A few exceptions where modifying the original is fine:

• Internal-only documents that won't be sent externally

• Documents where you're the sole author and have version control elsewhere

• Documents in a tracked system where the original is preserved automatically (DMS, cloud document management)

For everything else, copy first, stamp second.

Common problems and how to fix them

Problem 1 — White box around the stamp

Cause: The stamp image isn't a transparent PNG. It's a JPG with a white background, or a PNG that was saved without transparency.

Fix: Create a new stamp in the stamp maker — the default export is transparent PNG. If you must use an existing stamp image with a white background, remove the background using a free tool like remove.bg, then re-export as transparent PNG.

The same root cause and fix applies to signatures — see our guide on how to make a transparent signature for the equivalent workflow on signature images.

Problem 2 — Stamp looks blurry or pixelated

Cause: The stamp PNG was created at low resolution, and scaling it up on the PDF makes the pixelation visible.

Fix: Recreate the stamp in the stamp maker at a larger canvas size. Export at high resolution. The stamp will stay sharp when sized to fit the PDF.

Problem 3 — Stamp is too small to read

Cause: Most PDF editors insert images at their original pixel size, which can be tiny on a full-page PDF.

Fix: Use the corner handles to resize. A typical office stamp on a printed letter is around 30-40mm wide, which translates to about 120-160 pixels wide on a standard PDF page rendered at typical screen DPI. Make it large enough to read clearly without dominating the document.

Problem 4 — Stamp position shifts when opened on a different computer

Cause: Some PDF editors save inserted images in ways that other PDF viewers interpret slightly differently.

Fix: Flatten the PDF before sending it. Most editors have a "Flatten" option that bakes the stamp into the document permanently. Once flattened, the stamp position is locked across any viewer.

Problem 5 — Multi-page PDF only got stamped on one page

Cause: Most free tools stamp the page you place the image on, not all pages automatically.

Fix: Add the stamp to each page individually for small documents. For long documents needing the same stamp on every page, use the batch-stamp feature in paid Adobe Acrobat or in free PDF-XChange Editor's free tier.

Problem 6 — Can't add a stamp because the PDF is locked

Cause: The PDF has security restrictions preventing editing.

Fix: If you legitimately have authorization to modify the document, the owner can remove the restrictions with the original password. If you don't have authorization to modify it, you shouldn't be stamping it anyway — work with the document's owner instead.

Quick reference: which method to use

| Your situation | Best free method | |---|---| | You have Word, simple PDF | Method 2A (Word) | | Complex PDF with formatting | Method 2B (free online tools) | | You're on a Mac | Method 2C (Preview) | | Sensitive document, don't want to upload | Method 2C (Preview) on Mac, or Method 2A (Word) on Windows | | Multi-page batch stamping | Free PDF-XChange Editor or paid Adobe Acrobat | | One-off quick stamp | Method 2B (browser-based) is fastest |

Putting it together

The end-to-end workflow once you have your stamp PNG saved:

• Make a copy of the original PDF (`document.pdf` → `document-STAMPED.pdf`)

• Pick the placement method that fits your situation (Word, online tool, or Preview)

• Open the PDF copy in that tool

• Insert the stamp PNG, position it, resize it

• Save the stamped PDF

• Send the stamped version to whoever needs it; keep the original clean for your records

Total time after the first stamping: about 60 seconds per PDF.

Stamp types for different document purposes

A few common stamps and what they're used for:

• APPROVED / REJECTED / PENDING — workflow review stamps

• PAID / RECEIVED / PROCESSED — accounts payable and receivable

• DRAFT / FINAL / VOID — version and status marking

• CONFIDENTIAL / INTERNAL ONLY — distribution control

• Company seal or logo stamp — branding and authentication

• Date stamps — receipt and processing date tracking

For workflow-specific stamps (APPROVED, PAID, RECEIVED), the office workflow stamp templates cover the standard designs and conventions for each.

Create your transparent stamp now

The whole free workflow starts at the stamp maker. Design once, reuse forever. The PNG you create works on every future PDF you need to stamp — and on every other document type (Word, Google Docs, emails, web pages) as a bonus.

If you also need to add a signature to the same PDF, see our companion guide on creating a transparent signature. The two tools work the same way: design once, save the PNG, drop it on the document.

Related guides

• The free stamp maker — the tool itself

• Company seal vs company stamp — what to put on a stamp depending on its purpose

• How to make a transparent signature — same workflow for signatures

• Office workflow stamp templates — APPROVED, PAID, RECEIVED designs

• How ToolBody works — overview of the three-tool workflow