Stamp Border Remover

Uploads a stamp PNG, decodes it onto an off-screen canvas, and crops a fixed number of pixels off every edge to remove a uniform frame, ink-bleed border, or scan artifact strip, then lets you download the cropped PNG. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-26

Overview

Introduction

This tool trims a uniform-thickness border off every edge of a digital stamp image entirely in your browser, the inverse of adding a frame.

It's ideal for cleaning up scanner artifacts or a decorative frame that shouldn't be part of the final digital stamp.

What Is Stamp Border Remover?

A client-side border-trimming tool that crops a fixed pixel thickness off the top, bottom, left, and right edges of an uploaded stamp image.

It's the inverse operation of this category's border adder, applied to the common stamp cleanup workflow.

How Stamp Border Remover Works

You specify a thickness in pixels; the tool computes the new, smaller canvas size after removing that thickness from every side.

It then copies the remaining interior pixels directly into the smaller output buffer, leaving their color and alpha untouched.

When To Use Stamp Border Remover

Use it to strip a scanner bed edge or shadow strip that got captured along with a stamp scan.

It's also useful for removing a decorative box or frame around a stamp design when only the inner mark is needed.

Features

Advantages

  • Runs entirely client-side; the uploaded stamp is never sent to a server.
  • Simple single-value control trims all four edges consistently in one step.
  • No resampling means the remaining pixels are unchanged from the source.

Limitations

  • Only removes an equal thickness from all four sides; uneven borders need a manual crop instead.
  • A thickness larger than half the smaller dimension leaves nothing behind and is rejected.

Examples

Trim a scanner edge artifact

Input

A 300x300 stamp scan with a 10px dark edge strip, thickness 10

Output

A 280x280 PNG with the artifact removed

A consistent scanner-bed shadow is usually the same thickness on every side.

Remove a decorative frame

Input

A 400x400 stamp with a 25px ornamental border, thickness 25

Output

A 350x350 PNG containing just the inner stamp design

Trimming the frame isolates the stamp's actual mark for reuse elsewhere.

Best Practices & Notes

Best Practices

  • Measure the border's actual pixel thickness first using an image editor's ruler or the PNG dimensions finder for reference.
  • Check the preview after trimming to confirm no part of the stamp's design was cut off.

Developer Notes

The edge-trimming math lives in the shared png-border-remover lib function; this tool's lib file thinly wraps removeBorderFromPng rather than re-implementing the crop bounds calculation.

Stamp Border Remover Use Cases

  • Cleaning a scanner-bed artifact off a stamp scan
  • Removing a decorative frame to isolate a stamp's core design
  • Trimming a consistent ink-bleed margin from a photographed stamp

Common Mistakes

  • Setting a thickness that's too large and accidentally cropping into the stamp's actual design.
  • Assuming this can handle borders of different thickness on different sides.

Tips

  • If the border is fully transparent rather than a visible strip, use the stamp padding remover instead for an automatic trim.
  • For uneven borders, use the stamp cropper with manual coordinates.

References

Frequently Asked Questions