Which image formats are supported?
JPG, JPEG, PNG, WebP, and HEIC (iPhone) are supported.
FileLumo Tool
压缩图片
用质量滑块压缩 PNG、JPG 和 WebP，或使用精确的 20/50/100KB 门户模式。
Drag & drop your files
or click the button below to browse
Maximum 20 files
Features
- Exact KB mode for 20KB / 50KB / 100KB portal limits
- JPG, PNG, WebP, and HEIC (iPhone) supported
- Batch compress up to 20 images at once
- No signup, no watermark
How to Compress Images Free Online (Quality or Exact KB)
Shrink photos for email, websites, and strict portal caps. Use the quality slider for everyday sharing, or Exact KB mode when a form demands 20KB, 50KB, or 100KB. Free, no account.
When to use Compress Images Free Online
- Hit 20KB / 50KB / 100KB photo limits on exam and government portals
- Reduce image size before emailing photos or screenshots
- Optimize PNG and WebP assets for faster website loading
- Compress HEIC or JPG before converting to PDF
How it works
- 1Upload JPG, PNG, WebP, or HEIC images
- 2Pick quality slider or Exact KB (portal) mode
- 3Click Compress and wait for FileLumo to finish
- 4Download a single JPEG or a ZIP for batches
Exact KB vs quality slider
- Exact KB: binary-searches quality and downscales only if needed until size is under your cap
- Quality slider: you choose detail vs size when the portal does not care about a hard KB limit
- Dedicated landings: /compress-image-to-20kb, /compress-image-to-50kb, /compress-image-to-100kb
Before you upload to Compress Images Free Online
Check the file you are about to process, especially when it contains contracts, IDs, invoices, payroll details, legal drafts, school records, or client information. FileLumo is designed for quick no-signup workflows, but the safest document workflow still starts with choosing the right file and keeping an untouched original copy.
- Keep a master copy before editing, compressing, converting, or protecting a document
- Remove pages you do not need to share before uploading sensitive packets
- Use a clear filename for the downloaded result so drafts and final copies do not get mixed up
Privacy, limits, and output quality
Most PDF jobs are simple, but edge cases happen: very large scans, unusual fonts, password-protected files, embedded images, and old PDF versions can change the output. After processing, open the result once before sending it to a client, school, court portal, or upload form. Server-side workflows use TLS in transit. FileLumo does not store your files — download your result to keep a copy.
- Use medium or balanced settings first when quality matters more than the smallest possible file
- For strict upload limits, compare the final file size against the portal requirement before submitting
- For confidential documents, review your organization policy before using any third-party online tool
Frequently asked questions
Can I compress to exactly 50KB?
Yes. Use Exact KB mode or open Compress Image to 50KB. The file will be under your target.
Can I compress multiple images at once?
Yes. Upload up to 20 images in one batch and download a ZIP.
Do I need to sign up?
No. Image compression is free with no account required.
Do you store my files?
No. We don't store your files. Download your result to keep a copy. Temporary copies are cleared when you leave.
Helpful guides
Learn more about Compress Images Free Online
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