An iPhone saves photos as HEIC. A GoPro records in MKV. A scanner outputs TIFF. A client sends a DOCX but you need PDF. Format incompatibility is one of the most common friction points in digital workflows, and it is rarely about the content itself: it is about the container. This category brings together every conversion tool on the site, covering image formats (JPG, PNG, WebP, AVIF, HEIC, GIF, BMP, ICO, SVG, TIFF, RAW), video formats (MP4, WebM, MOV, AVI, MKV, FLV, WMV, TS, M4V), audio formats (MP3, WAV, FLAC, OGG, M4A, AAC, AIFF, WMA, Opus), and document formats (PDF, DOCX, EPUB, HTML, TXT, JPG). All conversions run in your browser using the Canvas API, FFmpeg compiled to WebAssembly, pdf-lib, pdfjs-dist, and mammoth.js.

When to Use These Tools

•Converting iPhone HEIC photos to JPG so they open on Windows PCs and Android devices
•Turning PNG logos into ICO files for browser favicons and Windows app icons
•Converting MKV video downloads to MP4 for playback on Apple TV and smart TVs
•Extracting MP3 audio from MP4 video files for podcast editing
•Converting DOCX documents to PDF for client delivery where editability is not needed
•Transforming RAW camera files (CR2, NEF, ARW, DNG) to JPG or PNG for web publishing

Benefits

•Supports over 50 format combinations across image, video, audio, and document types
•HEIC conversion uses heic2any for accurate color reproduction and metadata preservation
•Video conversion offers both fast remux (seconds, no quality loss) and full re-encode with resolution controls
•Audio conversion supports 14 format pairs with constant and variable bitrate options
•Document conversion uses mammoth.js for DOCX and pdf-lib for PDF assembly
•Batch conversion processes multiple files in one session with a ZIP download

Tips for Best Results

•Convert HEIC to JPG for universal compatibility: HEIC support outside Apple ecosystems is still inconsistent in 2025
•Use WebP for web images: it is 25 to 35% smaller than JPG and supported by all major browsers since Safari 14
•When converting video, check if a remux is available first: it takes seconds and preserves quality
•Convert RAW files to TIFF for editing, or to JPG for final delivery: avoid converting RAW to PNG as file sizes will be very large
•For SVG to PNG conversion, set the output resolution to 2x your target display size for retina screens
•Convert audio to MP3 at 192 kbps for general use, or AAC at 256 kbps for Apple ecosystem compatibility

Practical Examples

Real estate agent with iPhone photos

A real estate agent shoots property photos on an iPhone 15 in HEIC format. The MLS listing platform only accepts JPG. Converting 40 HEIC photos (each 1.5MB) to JPG at quality 90 produced 40 files averaging 900KB. Total time: under 30 seconds using batch conversion.

GoPro footage for Instagram

A travel creator had 12 GoPro clips in MKV format at 4K 60fps. Instagram requires MP4. Remux conversion (no re-encode) produced MP4 files in under 5 seconds each with zero quality loss. The clips uploaded directly to Instagram without re-encoding on their end.

Scanned archive from TIFF to WebP

A library digitized 300 historical photographs as 600 DPI TIFF files (each 18MB). Converting to WebP at quality 85 reduced each file to 2.1MB while preserving detail visible at 200% zoom. Total archive went from 5.4GB to 630MB.

Converting a Word contract to PDF

A freelance designer received a 6-page contract in DOCX format. The client needed a signed PDF. DOCX to PDF conversion using mammoth.js and jsPDF produced a 420KB PDF with preserved formatting, headings, and embedded signature image. The entire process took 4 seconds.

Common Mistakes to Avoid

•Converting PNG to JPG when transparency is needed: JPG does not support alpha channels, so transparent areas become white
•Re-encoding video when a remux would suffice: if the codec is already H.264, changing the container from MKV to MP4 takes seconds with no quality loss
•Converting lossy formats to lossless (JPG to PNG) expecting quality improvement: the JPG artifacts are baked in and the file becomes 5 to 10x larger
•Using GIF for video clips: MP4 is 10 to 50x smaller for the same content and supports audio
•Forgetting that SVG conversion to raster formats is resolution-dependent: always specify the output pixel dimensions

References and Further Reading

Frequently Asked Questions

Conclusion

Format conversion is the bridge between devices, platforms, and software. Whether you need HEIC to JPG for sharing, MKV to MP4 for playback, or DOCX to PDF for delivery, the tools above handle it in your browser. Pick the conversion you need, drag in your file, and download the result.