FormatOwlOnline Video Converter — MP4, MOV, MKV & WebM
Batch convert MP4, MOV, MKV and WebM videos. Adjust codec, resolution and frame rate, preview the output and download your files.
- Input
- MP4 · MOV · MKV · WebM
- Output
- MP4 · MOV · MKV · WebM
Up to 1 GiB per file and 20 files per batch. Conversion output is limited to 4 GiB per file.
MP4 with H.264 is the default. WebM uses VP9. Conversion processes the main video and default audio track; extra tracks, subtitles and attachments are not copied. SDR only; HDR is rejected.
Online Audio Converter — MP3, WAV, M4A & FLAC
Batch convert MP3, WAV, AAC, M4A, FLAC and OGG audio. Choose output format, bitrate, sample rate and channels, then listen and download.
- Input
- MP3 · WAV · AAC · M4A · FLAC · OGG
- Output
- MP3 · WAV · AAC · M4A · FLAC · OGG (Opus)
Up to 1 GiB per file and 20 files per batch. Conversion output is limited to 4 GiB per file.
MP3 at 192 kbps is the default. WAV and FLAC offer lossless output encoding; OGG output uses Opus. Valid bitrate and sample-rate combinations depend on the selected format.
Online Image Converter — JPG, PNG, WebP, AVIF & HEIC
Convert JPG, PNG, WebP, AVIF, GIF and HEIC to JPG, PNG, WebP or AVIF in batches. Choose quality and a background for transparent images.
- Input
- JPG / JPEG · PNG · WebP · AVIF · GIF · HEIC
- Output
- JPG · PNG · WebP · AVIF
Up to 50 MiB per file and 20 files per batch. Images are limited to 100 million pixels; animation limits also apply.
PNG is the default. JPG fills transparency with a chosen background; PNG, WebP and AVIF can preserve it. Animated inputs need explicit first-frame selection unless output is WebP. HEIC collections use the primary image.
Video to MP3 Converter — Extract Audio Online
Extract MP3 audio from MP4, MOV, MKV or WebM. Select an audio track and time range, preview the audio and export at 128, 192 or 320 kbps.
- Input
- MP4 · MOV · MKV · WebM
- Output
- MP3
Input files total up to 1 GiB. The video must contain an audio track. Exports are limited to 24 hours.
Select the audio track you need and optionally trim its time range. Higher MP3 bitrates create larger files and cannot restore missing detail from the original audio.
Convert by format
HEIC to JPG
Convert HEIC photos to JPG in batches of up to 20. Preview the primary image, adjust JPG quality and download individual images or a ZIP.
WebP to JPG
Convert WebP images to JPG online. Fill transparent areas with white or a chosen color, adjust quality, and download in batches.
MOV to MP4
Convert MOV videos to MP4 with H.264 selected by default. Adjust quality and resolution, preview your video, and download batch results.
M4A to MP3
Convert M4A audio to MP3 online, starting at 192 kbps. Adjust bitrate and channels, listen to the result and download individual files or a ZIP.
Helpful file guides
- VIDEO · SIZE & QUALITY
How to compress a video to a target file size
Choose a video size budget, understand bitrate and resolution tradeoffs, and compare a measured FormatOwl compression example.
Read guide - IMAGES · FORMAT & TRANSPARENCY
WebP to JPG: what happens to a transparent background?
Learn why JPG needs a background color, choose white or a custom fill in FormatOwl, and decide when PNG or WebP is a better output.
Read guide
Compress Files Online
Reduce video, audio, image and PDF file sizes. Compare formats, size limits and quality settings to choose the right file compressor.
View credits & pricing