FormatOwlOnline Video Compressor — MP4, MOV & WebM
Reduce MP4, MOV, MKV and WebM video size online. Choose a quality preset or target file size, preview the result and download MP4.
- Input
- MP4 · MOV · MKV · WebM
- Output
- MP4 (H.264 / H.265)
One video at a time, up to 1 GiB. A target that is too small for the duration can be rejected. Final size can vary slightly.
Start with Balanced. Use H.264 for broad playback compatibility. A target size uses two-pass encoding; a lower resolution can help when the bitrate budget is small. H.265 needs a compatible player.
Online Image Compressor — Batch JPG, PNG, WebP & HEIC
Compress JPG, PNG, WebP, GIF and HEIC images in batches. Keep the source format, transparency and supported animations, then preview and download.
- Input
- JPG / JPEG · PNG · WebP · GIF · HEIC
- Output
- JPG / JPEG · PNG · WebP · GIF · HEIC
Up to 50 MiB per file and 20 files per batch. Images are limited to 100 million pixels; animation limits also apply.
Balanced is the starting preset. Stronger compression trades fidelity for size where applicable. Image dimensions stay unchanged; compression is different from resizing.
Online Audio Compressor — MP3, WAV, M4A & FLAC
Reduce audio size by adjusting bitrate, sample rate and channels. Upload MP3, WAV, AAC, M4A, FLAC or OGG and export MP3 or M4A.
- Input
- MP3 · WAV · AAC · M4A · FLAC · OGG
- Output
- MP3 · M4A (AAC)
Up to 1 GiB per file and 20 files per batch.
Try 192 kbps for a starting comparison, 128 kbps for a smaller file, or 64 kbps when size matters more than detail. Listen to speech and music separately. Actual AAC bitrate varies.
Online PDF Compressor — Reduce PDF Size
Reduce PDF size with light, balanced or strong compression. Preview pages, retain existing text and structure, and download individually or in a ZIP.
- Input
- Output
Up to 50 MiB and 1,000 pages per file, 20 files per batch. Encrypted and digitally signed PDFs are rejected.
Light optimizes structure. Balanced and Strong also optimize supported embedded images. Existing text is kept; compression does not add OCR to a scanned document.
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 - PDF · COMPRESSION & CONTENT
Why is my PDF still large after compression?
Understand text-heavy and scanned PDFs, choose a compression preset, and learn why some PDFs return unchanged without adding OCR.
Read guide
Online File Format Converter
Convert video, audio and image formats online. Compare supported inputs and outputs, or go straight to HEIC to JPG, WebP to JPG, MOV to MP4 and M4A to MP3.
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