Best Free File Converters Online (2025)
Convert, compress, and merge PDFs, images, videos, and data files for free in your browser. No uploads, no sign-ups, fully private.
Guide Overview
File conversion should not require downloading sketchy software or uploading sensitive documents to unknown servers. Every converter on this page runs entirely in your browser using client-side processing. Your files never leave your device, making these tools safe for business documents, personal photos, and everything in between.
Focus: free browser-based file conversion, no upload to server
Privacy-First File Conversion in Your Browser
Most online converters upload your files to remote servers for processing, which raises serious privacy concerns for business documents, financial records, and personal files. Our converters use WebAssembly and client-side JavaScript to process everything locally in your browser tab. Nothing is transmitted, nothing is stored, and the processed file is available for download instantly. This approach is not just more private, it is also faster because there is no upload and download round trip.
PDF Tools: Merge, Compress, and Convert
PDFs are the universal business document format, but working with them usually requires paid software. Our PDF merger combines multiple files into a single document with drag-and-drop reordering. The PDF compressor reduces file size by optimizing images and removing unnecessary metadata, which is essential for email attachments and web uploads. The PDF-to-Word converter extracts text and formatting so you can edit documents that were previously locked in PDF format.
Image Conversion and Compression
Modern devices create images in formats that are not always compatible with every platform. iPhones shoot in HEIC, cameras output RAW files, and web designers need WebP for performance. The image format converter handles all common conversions including HEIC to JPG, PNG to WebP, and SVG to PNG. The image compressor reduces file sizes by 50 to 80 percent with minimal visible quality loss, which speeds up website loading times and reduces storage costs.
Video and Audio Compression
Video files are the largest files most people work with, and sharing them via email or messaging apps often requires significant compression. Our video compressor reduces file sizes while preserving acceptable quality for sharing and playback. The audio format converter handles conversions between MP3, WAV, AAC, and other common formats. Both tools process files locally, which means even large video files do not need to be uploaded to a server.
Data File Conversion: JSON, CSV, and Archives
Developers and analysts frequently need to convert between data formats. The JSON-to-CSV converter transforms structured data into spreadsheet-compatible format and vice versa, handling nested objects and arrays intelligently. The ZIP compressor creates compressed archives from multiple files for easier sharing and storage. These tools are especially useful when moving data between systems that expect different formats or when preparing datasets for analysis.
Tools in This Guide
Use these tools in sequence based on your workflow needs.
PDF Merger
Merge multiple PDFs into a single document.. Free online, browser-based tool with instant results and no signup.
Use tool →PDF Compressor
Reduce PDF file size for sharing and uploads.. Free online, browser-based tool with instant results and no signup.
Use tool →PDF to Word Converter
Convert PDF documents to editable Word format.. Free online, browser-based tool with instant results and no signup.
Use tool →Image Format Converter
Convert images between JPG, PNG, and WebP formats. Resize, adjust quality, batch convert — all in your browser.
Use tool →Image Compressor
Compress JPG/WEBP images in your browser with quality and max-width controls.. Free online, browser-based tool with instant results and no signup.
Use tool →Video Compressor
Compress video files to smaller sizes for faster upload and sharing.. Free online, browser-based tool with instant results and no signup.
Use tool →JSON to CSV / CSV to JSON Converter
Convert between JSON and CSV formats instantly. Supports custom delimiters, nested objects, and file upload.
Use tool →HEIC to JPG Converter
Convert HEIC photos to JPG for broader compatibility.. Free online, browser-based tool with instant results and no signup.
Use tool →Audio Format Converter
Convert between MP3, WAV, AAC, FLAC, and more audio formats.. Free online, browser-based tool with instant results and no signup.
Use tool →ZIP Compressor
Compress files into ZIP archives.. Free online, browser-based tool with instant results and no signup.
Use tool →Frequently Asked Questions
Are my files uploaded to your servers?
Is there a file size limit for conversions?
What image formats are supported?
How much can the PDF compressor reduce file size?
Can I convert multiple files at once?
Last updated: June 1, 2025