Compress any image to an exact file size. Resize your image size from MB to kB.
Your files never leave your device. All compression happens locally in your browser.
MB2kB is a free online image compressor that lets you reduce image file size to any specific target you need. Whether you want to compress an image to 50 kB, 100 kB, 200 kB, or any other size, MB2kB makes it simple. Just upload your image, enter your desired file size, and the tool handles the rest.
If you have ever tried uploading a photo to a government website, job portal, or college admission form, you know how frustrating size limits can be. These portals are very strict about file sizes, and they will reject your upload if the image is even slightly over the limit. That is exactly the problem MB2kB solves.
What makes MB2kB different from most other image compressors is that everything happens locally in your browser. Your images are never uploaded to any server. The compression runs entirely on your device, which means your photos stay private and the process works even on slower internet connections.
So whether you need to compress an image from MB to kB for an online form or just want to reduce image size for email, MB2kB is the quickest way to get the job done.
There are plenty of image compressors out there, but here is what makes MB2kB stand out from the rest.
Your images never leave your device. All compression happens right inside your browser for complete privacy.
Set a precise target in kB or MB. Need exactly 100 kB for a form? MB2kB hits it every time.
No accounts, no sign-ups, no email verification. Just open, drop, compress, and download.
Works with all major image formats. The compressor handles format detection automatically.
No usage limits, no watermarks, no hidden charges. Compress as many images as you need.
Runs in any browser on phones, tablets, laptops, and desktops across all operating systems.
Compressing images with MB2kB is quick and straightforward. Here is a step by step walkthrough.
Drag and drop your image into the upload area, or click to browse and select a file from your device. MB2kB supports JPG, JPEG, PNG, and WebP formats, so most images will work right away.
Enter the file size you need in the input box. You can choose between kB and MB using the dropdown. For example, if a form requires a photo under 100 kB, just type 100 and select kB.
Click the Compress button and MB2kB will start reducing your image to the target size. The entire process happens locally in your browser, so it is fast and your image stays on your device.
Once the compression is done, you will see a before and after comparison along with the new file size. Click the Download button to save the compressed image to your device.
If you need to compress images on a regular basis, check out our Image Compressor mobile app. It is available for both Android and iOS, and it also supports compressing multiple images at once.
People use MB2kB for all kinds of situations. Here are some of the most common ones.
SSC, UPSC, and banking portals require photos between 50 kB and 100 kB.
Profile photos and resume images for Naukri, LinkedIn, and career pages.
Photos and scanned documents for university admission portals.
Reduce photo sizes so your emails send without bouncing back.
Faster page loads, better SEO rankings, and improved user experience.
Keep photos looking sharp while staying within platform guidelines.
Image compression works by reducing the amount of data stored in a file. With lossy compression (which is what MB2kB uses for JPEG images), the tool removes small details that the human eye is unlikely to notice. The result is a much smaller file that still looks great to most people. The level of compression depends on how small you need the file to be.
File size matters because many websites and online forms set strict upload limits. If your image is 2 MB but the form only accepts files under 100 kB, you need a way to bridge that gap. That is where an image compressor like MB2kB comes in. It lets you target the exact size you need instead of guessing and re-compressing over and over.
Want to learn more about how this works? Check out our articles on how image compression works and the differences between JPEG, PNG, and WebP formats.
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Read MoreFor those searching for "optical communication systems john gowar pdf," several academic and archival resources are available:
Engineers frequently reference Gowar for established methodologies in system design:
Whether you are a student looking for a PDF version for study or an engineer needing a refresher on link power budgets, this article provides a comprehensive overview of the book's core concepts and its enduring relevance. optical communication systems john gowar pdf
: While modern systems have advanced significantly, Gowar’s early introduction to coherent detection and unguided (free-space) optical communication remains theoretically sound. Why It Remains a Standard Reference
: Comprehensive sections on attenuation and dispersion (material, waveguide, and modal), which are the two primary factors limiting fiber-optic range and speed. For those searching for "optical communication systems john
The book is structured to provide "single-source coverage" of the primary elements that make up an optical link. Gowar emphasizes the interplay between the following components:
: Deep dives into the physics of semiconductor light sources, specifically LEDs and laser diodes. Gowar covers their drive circuits, modulation characteristics, and the transition between spontaneous and stimulated emission. The book is structured to provide "single-source coverage"
: Determining the total system bandwidth by accounting for the rise times of the transmitter, fiber (dispersion), and receiver.
: Offers a digital loan of the full 1984 edition.
John Gowar’s Optical Communication Systems is widely regarded as a foundational textbook in the field of optoelectronics and fiber-optic technology. First published in 1984 with an extensive update in 1993, this classic text bridges the gap between fundamental physics and practical communication engineering.