The Fastest & Most Secure Image Converter
All conversions are processed in your browser. Files are never sent to the server.
Format
Quality
Security & Privacy
100% Local Processing
StartLoom is different from traditional image conversion sites. Your uploaded images are never sent to the server. All conversion tasks are processed instantly within your web browser's memory and disappear without a trace as soon as you close the tab. Process sensitive personal photos or business documents with peace of mind.
Frequently Asked Questions (FAQ)
Q. Why does the file size increase after conversion?
This can happen if the image is already optimized or the Quality value is set too high. Generally, 80-90% is recommended. If the size increases, try lowering the quality slider.
Q. Can I convert multiple files at once?
Yes, you can convert multiple files by dragging and dropping or selecting them all at once. After conversion, use the 'Download All' button to get your results.
Q. Does it work on mobile?
StartLoom is built as a responsive web app and works identically on all mobile device browsers, including iPhone and Android.
WebP
WebP is an image format announced by Google in 2010 to dramatically improve web page loading speeds. It is designed to perfectly replace the most commonly used JPEG, PNG, and GIF formats on the web. Through lossy compression, it maintains visual quality at a level where human eyes can barely perceive any degradation from the original, while drastically reducing file size by an average of 25-34% compared to JPEG. Furthermore, it perfectly supports alpha channel features for transparent backgrounds while being over three times smaller than PNG. Thanks to this overwhelming compression efficiency, it not only reduces website server traffic costs but also accelerates page rendering speeds, playing a direct and essential role in improving Google Search Engine Optimization (SEO) scores.
AVIF
AVIF (AV1 Image File Format) is a next-generation image format born from the latest open-source video codec (AV1) technology developed by AOMedia, a consortium of the world's leading tech companies including Netflix, Google, and Amazon. It boasts the most overwhelming compression efficiency among existing technologies, and can achieve the same image quality with about 20-30% less file size than even the highly acclaimed WebP. By supporting rich 10-bit and 12-bit color information, HDR (High Dynamic Range), and wide color gamut, it provides professional-grade image quality that extracts 100% of the performance of modern displays. However, compression requires somewhat complex decoding calculations, and compatibility issues may arise in older browsers like Internet Explorer. Therefore, it is the dream format most suitable for modern web projects that require top-tier quality and extreme file size reduction.
Typical online image conversion sites use an insecure method where, once you upload a file, the photo is completely transmitted to a remote server computer, processed there, and then a download link is provided back to you. This is a business model intended to cover massive server maintenance costs through advertisements or collecting user data. It inherently carries a fatal risk that confidential company documents, private personal photos, or copyrighted creations could be leaked to the internet without permission due to server hacking or administrator negligence. StartLoom uses innovative WebAssembly technology to fundamentally block these security threats. The moment you select a file, without a single step of data traveling over the internet to a server, all conversion calculation processes are 100% instantly handled solely within the isolated sandbox memory space built into your laptop or smartphone's browser. This is perfectly identical in principle to installing and running an offline program (e.g., Photoshop) or an app. Once the conversion is complete, the results are instantly generated from memory and downloaded. The moment you close the browser tab or refresh, even the history of the task is permanently destroyed. StartLoom developers or third parties boast a complete Zero-Trust architecture where there is absolutely no way to access, view, or store what files you converted.
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Unlimited Batch Processing without Hidden Fees
Professional designers or online store operators have to process tens to hundreds of photos every day. There are absolutely no annoying restrictions like 'limit of 10 photos per day' or '5MB maximum size per conversion' found in other services. Just drag and drop hundreds of images with your mouse at once, and it will elegantly and swiftly batch-convert all files in the background as much as your PC performance allows.
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Uninterrupted Persistence even Offline (PWA Support)
Don't stall your work even if the cafe's Wi-Fi drops or you're passing through a dark tunnel on a train. StartLoom, equipped with Progressive Web App (PWA) technology, immediately saves its core engine to the browser cache upon the very first visit. After that, it provides the true magic of experiencing perfectly identical image conversion performance just by opening the site, even on an airplane with the internet cable completely unplugged.
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Intuitive, Elegant UI and User-Friendly Quality Controls
Instead of visually complex and messy settings panels, it is equipped with beautiful slider controls that anyone can intuitively understand. You can discover the perfect balance—the sweet spot—by seamlessly adjusting the Quality in real-time down to 1% increments, determining exactly how dramatically to reduce the file size without blurring the original file's pixels.