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The 300KB target is set
This page opens with the maximum file size already fixed at 300KB, so there is nothing to configure.
Compress Image to 300KB
Roomier limit that preserves more detail. Fast, 100% private, and processed directly in your browser with zero server uploads.
Compress images to 300KB or less
Output is optimized JPG. Transparent areas are placed on white.
Drop images here, or click to choose files
Processed locally in your browser · Zero server uploads
SupportsJPEG, PNG, WebP, AVIF, HEIC, GIF, BMP, TIFF
TargetOptimized JPG compressed to ≤ 300KB
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In-Browser Compression
What does compressing to 300KB mean?
A 300KB limit leaves enough headroom that most images keep their original pixel dimensions — the quality search alone usually gets there. That makes it a good target for documents, screenshots and photos containing text or fine edges, where downscaling would be the first thing you notice. Compression runs locally in this browser tab.
Everyday Upload CompressionForms & Web Uploads
Standard workflow: multi-megapixel phone photos and document scans compressed to just under 300KB each, with the original pixel dimensions kept wherever the quality search allows.
Compression Architecture100% In-Browser Memory Pipeline
Source Imageany size
JPG · PNG · WebP
Decoded directly via the browser’s hardware-accelerated image pipeline into raw pixels.
Engine: Browser NativeZero upload
Local Memorycanvas / RAM
MozJPEG Target Search
The browser’s fast encoder brackets the quality, then MozJPEG refines it — interpolating from each measured size until the file sits just under 300KB.
RAM Security100% Private
Result.jpg
≤ 300KB
Optimized JPG at or under the limit, with before/after size, pixel dimensions and reduction shown per file.
Single file or ZIPDirect export
End-to-end local architecture: files are processed strictly within your device’s memory and never leave your computer or phone.
For the full walkthrough — why the budget decides the resolution, how MozJPEG buys back a quarter of it, and why quality alone is the wrong dial to turn — read How the Image Compressor works.
How to compress an image to 300KB
Compress your files in three simple steps directly in your browser:
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Add your images
Drop a single image or a whole batch. The quality search starts immediately, locally, without uploading the files.
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Check and download
Review the output size, pixel dimensions and reduction percentage, then save individual JPG files or the whole batch as a ZIP.
Key Advantages
Why compress to 300KB locally?
Hit the limit your form asks for without handing the photo to a cloud service first.
Privacy & SecurityZero Uploads
100% Private In-Browser Processing
Your photo is decoded, re-encoded and resized inside this browser tab’s memory. No file is sent to a remote server — which matters most for exactly the documents that carry upload limits: ID photos, passport scans and signatures.
Zero network transmission — complete local security
Fidelity & EngineOptimized JPG
The Clearest Result That Fits
Rather than applying one fixed quality, the tool first works out how many pixels 300KB can afford — a photo squeezed into a budget too small for its resolution comes back blocky, so resolution is part of the budget, not separate from it. It then searches for the highest MozJPEG quality that still lands under 300KB, which is 25-30% higher than the browser’s own encoder could hold at the same file size.
Dimensions preserved where possible — no watermarks
Batch WorkflowZIP Export
Many Files, One Limit
Drop a whole folder and every image is compressed to the same 300KB cap, each with its own before/after readout. Save them one at a time or pack the finished batch into a single ZIP, assembled in browser memory.
SpecificationsStandards
Output & Privacy Guarantees
- •Size: The result is at or below 300KB; the UI says so plainly when a photo cannot get there.
- •Transparency: JPEG has no alpha channel, so transparent pixels composite onto white.
- •Metadata: EXIF & GPS location tags are stripped during re-encoding.
Standard baseline JPEG, accepted by every upload form
Continue with another image tool
After checking an image, choose a tool for the change you need. Each tool has a different purpose.
Image Format Converter
Change the image file format, such as PNG to JPG or WebP. This is different from converting pixels to print units.
Explore tool
Image Resizer and Social Media Sizes
Change pixel width and height for a website, print layout or social media preset. Enlarging an image does not restore missing detail.
Explore tool
Metadata Remover
Need to strip or edit EXIF before sharing? Open Metadata Remover to remove GPS, camera data and other hidden fields.
Explore tool
Image Size Finder
Check pixel width, height, megapixels and aspect ratio instantly for one image or a full batch.
Explore tool
Other target sizes
A different form, a different limit — each size has its own ready-to-use page.
300KB image compression FAQ
How do I compress an image to 300KB?
Drop your image into the tool above. It automatically lowers the JPG quality (and resizes if needed) until the file is 300KB or smaller, then you download it. Everything runs in your browser — nothing is uploaded.
Is it free?
Yes — no signup and no watermark. Processing capacity depends on your device and browser.
Why would I need an image under 300KB?
Many forms cap upload size — exam and visa portals, job applications, government sites and email attachments. Roomier limit that preserves more detail.
Will the image still look okay?
The tool keeps quality as high as possible while hitting the size target. For very small targets on large photos it will also reduce the dimensions so the result stays clean rather than blocky.
Can I compress several images to 300KB at once?
Yes. Drop a batch and every file is compressed to the same 300KB limit. Download them individually or all together as a single ZIP archive.
What format is the result?
An optimized JPG. JPEG has no alpha channel, so transparent areas in a PNG or WebP source are placed on white. EXIF and GPS metadata are dropped because the file is re-encoded from raw pixels.
Free & Private In-Browser Tool
Compress Image to 300KB Online Now
Fast, 100% private, and completely free in-browser compressor. Drop your images and download optimized JPG files under 300KB in seconds.