Convertlo converts images, documents, audio, and video entirely in your browser — nothing ever leaves your device.
We built Convertlo because file conversion should be simple, fast, and private. Every other converter uploads your files to a server — which means your data is exposed in transit, stored on someone else's machine, and processed at the speed of their network.
Convertlo uses modern browser APIs (WebAssembly, Canvas, Web Audio API, FFmpeg.wasm) to run all conversion logic directly on your device. Your files never leave your browser tab. There is no server, no upload, and no waiting in a queue.
Files stay on your device. Zero uploads, zero server processing, zero data exposure.
Convert any file size without restrictions. No daily cap, no file count limit, no paywall.
190+ converter tools — all free, forever. No account required to start converting.
Browser-based means conversion starts immediately — no upload, no queue, no delay.
All conversion happens locally in your browser using battle-tested open-source libraries:
The file is read by your browser using the File API — it never touches the internet.
Images use Canvas and Pica. Documents use PDF.js, SheetJS, and Mammoth. Audio and video use FFmpeg.wasm compiled to WebAssembly.
A download link is created from a local Blob URL. No file ever leaves your device at any stage.
We cover image formats (JPG, PNG, WebP, AVIF, HEIC, SVG, GIF, BMP, TIFF, and more), document formats (PDF, DOCX, XLSX, CSV, HTML, TXT, JSON, PPTX, and more), audio formats (MP3, WAV, FLAC, AAC, OGG, WMA, OPUS, and more), and video formats (MP4, WebM, MOV, MKV, AVI, WMV, and more).
Our content is written and reviewed by people who use these tools themselves. Every guide, tutorial, and comparison article on this site is researched by our editorial team, fact-checked for technical accuracy, and updated when formats or browser support changes.
File format specialists and web technology writers. We research compression algorithms, browser compatibility, and conversion quality to bring you accurate, actionable guides.
Follow Convertlo for file format tips, compression guides, and new tool announcements:
Found a bug? Have a suggestion for a new converter? We read every message.
Reach out via our social channels above, or open an issue on our GitHub repository. We typically respond within 24–48 hours.
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