About Us
File Conversion That Respects Your Privacy
Convertlo converts images, documents, audio, and video entirely in your browser — nothing ever leaves your device, no account required, and no file size limits.
Why We Built Convertlo
File converters have been around for decades. Most of them follow the same pattern: upload your file to a server, wait for it to process, then download the result. That model made sense in 2005 when browser technology couldn't handle local processing. In 2024, it no longer needs to work that way.
Modern browsers can run WebAssembly, access the GPU, decode video, and do things that would have required a dedicated desktop application just a few years ago. We looked at that capability and asked: what if the entire conversion pipeline ran in your browser tab? Your files would never travel over the network. Conversion would start instantly. There would be nothing to upload, no server to wait for, and no privacy risk.
That is Convertlo. We built it to prove that a file converter can be simultaneously free, private, unlimited, and faster than any server-based alternative — because all the work happens on hardware you already own.
Our Mission
Our goal is straightforward: give anyone with a browser access to a professional-grade file conversion toolkit, permanently free, with no strings attached. No account, no trial period, no watermark on your converted files, and no daily limit on how many files you can convert.
🔒
Privacy First
Files stay on your device. Zero uploads, zero server processing, zero data exposure. We cannot access your files because they never reach us.
⚡
No Limits
Convert files of any size without restrictions. No daily cap, no file count limit, no paywall. Large video files, multi-page PDFs — all handled locally.
🌍
Always Free
190+ converter tools, all free, forever. We are funded by non-intrusive advertising, not by charging users or selling data.
🏎️
Instant Start
Conversion begins the moment you drop a file — no upload progress bar, no queue, no waiting. Your hardware processes it immediately.
How It Works Under the Hood
Convertlo uses a combination of browser-native APIs and open-source libraries compiled to run locally. Here is what powers each category:
-
Images — Canvas API + Pica
The HTML5 Canvas reads your image, converts it to the target format (WebP, AVIF, JPG, PNG, etc.), and generates a local download URL. Pica handles high-quality resampling for resizing. Zero network activity.
-
Documents — PDF.js + SheetJS + Mammoth
PDFs are parsed by Mozilla's PDF.js library running in your browser. Spreadsheets use SheetJS for XLSX/CSV/JSON conversion. DOCX files are handled by Mammoth.js. All run entirely client-side.
-
Audio & Video — FFmpeg.wasm
FFmpeg — the gold-standard open-source media processing library — is compiled to WebAssembly so it runs directly in your browser. The same engine professionals use for video encoding, available without installation.
-
Background Removal — @imgly/background-removal
Our Remove Background tool uses a neural network model that runs locally in your browser via WebGL. The AI model is cached after the first download so it works offline on subsequent uses.
-
1
You select a file
The file is read by your browser's File API. It is loaded into memory on your device — no data leaves your machine at this stage or any subsequent stage.
-
2
The browser processes it
The appropriate library (Canvas, FFmpeg.wasm, PDF.js, etc.) processes your file entirely in your browser tab using your device's CPU and GPU.
-
3
You download the result
A download link is generated from a local Blob URL. Clicking it saves the converted file to your device. The file never touches any external server at any point.
Our Privacy Commitment
Privacy is not a feature we added as an afterthought — it is the architectural foundation of how Convertlo works. The following are not policies we can change; they are technical facts about how the software is built:
- ✓
No uploads ever. Convertlo has no file upload endpoint. There is no server-side code that accepts files. Your files cannot reach our servers even if you wanted them to.
- ✓
No file metadata logged. We do not log filenames, file sizes, or any information about what you convert. Standard web analytics (page views, session duration) are collected via Google Analytics, but file content is never involved.
- ✓
GDPR and CCPA compatible. Because no personal file data is processed on our servers, Convertlo does not create the data controller obligations that server-based converters do under privacy regulations.
- ✓
Offline capable. After your first visit, image and document converters work without an internet connection. Your conversion activity is invisible to the network once the page assets are cached.
- ✓
Open-source libraries. Every library Convertlo uses (FFmpeg, PDF.js, SheetJS, Mammoth, Pica, @imgly/background-removal) is open-source and publicly auditable. We do not use any proprietary black-box processing.
What We Cover
0
files uploaded anywhere
Convertlo covers four major categories: Images (JPG, PNG, WebP, AVIF, HEIC, SVG, GIF, BMP, TIFF, and more), Documents (PDF, DOCX, XLSX, CSV, HTML, TXT, JSON, and more), Audio (MP3, WAV, FLAC, AAC, OGG, M4A, OPUS, and more), and Video (MP4, WebM, MOV, MKV, AVI, WMV, FLV, GIF, and more). We also offer utility tools — an image compressor, a background remover, and a growing library of format guides in our blog.
Our Editorial Team
The guides, tutorials, and comparison articles on Convertlo are written by our editorial team — people who work with file formats professionally and test every tool they write about. We hold ourselves to a few specific standards:
- → Every claim about file size reduction or quality difference is tested with real files, not sourced from marketing copy.
- → Browser compatibility tables are verified against current browser release notes, not assumed from outdated sources.
- → Articles are updated when format standards change (e.g., when Safari adds WebP support, or when a new codec ships in Chrome).
- → We do not accept sponsored rankings or paid placements in comparison articles. Our "vs" pages reflect genuine technical differences.
✍️
Convertlo Editorial Team
File format specialists and web technology writers. We research compression algorithms, browser compatibility, and conversion quality benchmarks to bring you accurate, actionable guides.
Frequently Asked Questions
Is Convertlo completely free to use?
Yes. Every tool on Convertlo is free with no limits, no watermarks, and no account required. There is no premium tier or paid upgrade. We are supported by non-intrusive display advertising, which means the conversion tools stay free indefinitely.
Do you store or keep copies of my files?
No. Convertlo does not upload, transmit, or store any of your files. All conversion happens locally in your browser using HTML5 Canvas, WebAssembly, and other browser-native APIs. Your files never leave your device at any stage — not even temporarily.
Is Convertlo safe for sensitive or confidential documents?
Yes, and this is by design. Because no files are uploaded to any server, there is no point of interception or storage. Your sensitive PDFs, contracts, medical images, or private photos are processed entirely on your own hardware. Even Convertlo's developers have no access to what you convert.
Does Convertlo work on iPhone and Android?
Yes. Convertlo works in any modern browser — Chrome, Safari, Firefox, or Edge — on any device. On iPhone, the HEIC to JPG converter is one of the most-used tools on the site. On Android, all image, audio, and document converters work fully. Video conversion (which uses FFmpeg.wasm) is best on desktop or newer Android browsers with sufficient memory.
Can I use Convertlo offline?
Yes. Convertlo uses a service worker to cache its core assets on your first visit. After that, most image and document converters work without an internet connection. The AI background removal model is also cached locally after the first download.
Is there a file size limit?
There is no hard file size limit imposed by Convertlo. The practical limit depends on your device's available RAM. Most modern devices handle images up to 50 MB, documents up to 100 MB, and video files of several hundred MB without issues. Very large video files (over 1 GB) work best on desktop browsers where memory is not constrained.
Find Us Online
Follow Convertlo for file format tips, compression guides, and new tool announcements:
Contact & Feedback
Found a bug? Have a suggestion for a new converter or format we should support? We genuinely read every message and prioritise tool requests that come up frequently.
Reach out through our social channels above, or visit our contact page. For press or business enquiries, contact us through our Facebook page. We typically respond within 24–48 hours.