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ResizeInKB
Compress & Resize Images in KB

Compress PNG Images Online

Shrink PNG files with background transparency preserved for web design, apps, and logos.

Drop photo here, or or browse

Supports JPEG, PNG, WebP & GIF up to 100 MB • 100% Free

✨ Select 1 or Multiple Photos at once
OR
100% Free ToolPNG CompressorLossless & Lossy PNG

Compress PNG Images Online

Shrink PNG files with background transparency preserved for web design, apps, and logos.

Author & Technical ReviewerVerified by Frontend Performance Team

Strict 100% In-Browser Binary Compression

Tested on 50+ official Indian exam engines (SSC, UPSC, IBPS, NTA, Passport Seva). Zero server upload, zero data collection.

100% Free & 100% Private Secure

PNG images offer sharp graphic edges and transparent backgrounds, but often carry heavy file sizes. ResizeInKB optimizes PNG color palettes and palette quantification to shrink file sizes significantly while retaining transparent layers.

How to Compress PNG Images Online

  1. 1Upload your PNG file.
  2. 2Choose PNG format under settings.
  3. 3Set desired target size or adjust dimensions.
  4. 4Download your light, transparent PNG.

Target Specifications

FormatPNG (Portable Network Graphics)
TransparencyFull Alpha Channel Preserved
Key Advantages:
Alpha channel transparency preserved
Substantial size reduction for web graphics

Official Portal Upload Criteria Comparison

Govt & College Forms
Exam / Portal NamePhoto LimitSignature LimitDimensionsRequired Format
SSC (CGL/CHSL/MTS)20 KB - 50 KB10 KB - 20 KB3.5 x 4.5 cmJPG / JPEG
UPSC Civil Services20 KB - 300 KB20 KB - 300 KB350x350 px minJPG / JPEG
IBPS Bank Exams20 KB - 50 KB10 KB - 20 KB200x230 pxJPG (Black Ink)
NEET / JEE (NTA)10 KB - 200 KB4 KB - 30 KB4x6 PostcardJPG / JPEG

How Client-Side Image Binary Compression Works Under the Hood

When you select a target size (e.g., 20KB or 50KB), ResizeInKB executes an in-browser binary search algorithm using the HTML5 HTMLCanvasElement.toBlob() API. It dynamically adjusts JPEG quantization matrices and pixel dimensions directly inside your browser's V8 JavaScript engine memory. Because no HTTP requests send image data across the network, your processing is instant, works offline, and keeps your private photos completely secure.

Frequently Asked Questions

No, transparent PNG channels are preserved during compression.
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