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ResizeInKB
Compress & Resize Images in KB

Batch Image Compressor in KB

Compress and resize multiple images simultaneously to target KB sizes in one click.

Drop photo here, or or browse

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

✨ Select 1 or Multiple Photos at once
OR
100% Free ToolBatch CompressorBulk Image Processing

Batch Image Compressor in KB

Compress and resize multiple images simultaneously to target KB sizes in one click.

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

Processing images one by one can be time-consuming. ResizeInKB supports batch mode, allowing you to drag & drop multiple photos and compress them all to a target KB size (e.g. 100KB or 50KB) in seconds.

How to Batch Image Compressor in KB

  1. 1Select multiple images from your computer or phone.
  2. 2Set your desired target KB size for all files.
  3. 3Click Compress All to process images concurrently.
  4. 4Download all compressed photos as individual files or a ZIP archive.

Target Specifications

Batch LimitUnlimited files per session
Processing SpeedConcurrent client-side parallel processing
Download OptionsSingle file downloads & ZIP archive
Key Advantages:
Bulk parallel processing
ZIP file download option
Zero server upload latency

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

You can set a global target size like 50KB or 100KB for the whole batch, or fine-tune individual target sizes for specific files in the queue.