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Video Converter

Convert videos between MP4, WebM, MKV and MOV. Drop in one or more files, pick the target format and quality, follow the encoding progress, and download the results one by one or all at once.

Everything runs locally in your browser. Your data never leaves your device.

Upload

Drop videos here

MP4, MOV, WebM, MKV, AVI and more. Click to choose files.

They never leave your browser.

Convert to

Plays practically everywhere and encodes fastest here. The safe default.

Downscaling caps the short edge (1080p, 720p, 480p) and keeps the aspect ratio. Videos smaller than the cap are never upscaled.

Encoding runs on your device and is much slower than a desktop app. A long video can take several minutes, WebM the longest.

Next steps

Send this tool's output straight into another tool.

Video Compressor

Shrink a video file right in your browser. Pick a quality level or a target size, optionally scale the resolution down, and compare the size before and after with a preview of the result.

videomediacompress

Video Trimmer

Cut a section out of a video on a frame-accurate timeline with a live preview. Drag the start and end handles, preview just your selection, and export either with the original quality kept or re-encoded to MP4 or WebM.

videomedia

Hash Generator

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

devsecurity

Checksum Validator

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

devsecurity

Data Compressor

Compress text or a file with gzip, deflate, brotli or Zstandard and see the size before and after, the compression ratio and how long it took. One click tries every method and recommends the smallest result.

devcompress

Data Decompressor

Decompress gzip, deflate, brotli or Zstandard data from a file or pasted Base64 and read the result as text or download it. Detects the format from the magic bytes where possible, with a manual override.

devcompress

Hex Viewer

Inspect any file or text as a hex dump with offsets, byte values and an ASCII column. Jump to an offset, search for bytes or text, select a range to see it decoded as integers and strings, and copy or download the dump.

dev

Video Inspector

See everything about a video file: duration, resolution, aspect ratio, frame rate, codecs, bitrate, container details and audio tracks, with a frame preview and a per-track breakdown. Reads MP4, WebM, MKV, MOV and more.

mediavideo

Video to Frames

Extract still frames from a video. Grab every frame, every Nth one or one per second, or step through and pick single frames by hand. Choose PNG, JPEG or WebP for the output and download everything as a zip.

mediavideoimageconverter

About the Video Converter Tool

This tool converts videos between MP4, WebM, MKV and MOV. Drop in one file or a whole batch, pick the target format and a quality preset, and convert. Each file shows its own progress bar, and the results download one by one or all together as a zip.

MP4, MKV and MOV encode with H.264 and AAC audio, WebM with VP9 and Opus. Quality is CRF based: three presets cover most cases, and a custom option exposes the raw CRF value for anyone who wants exact control. An optional downscale to 1080p, 720p or 480p keeps the aspect ratio and never upscales.

What you can do

  • Convert MOV to MP4, MKV to MP4 or WebM to MP4.
  • Convert MP4 to WebM for the web, or to MKV and MOV.
  • Batch convert many videos in one go.
  • Pick a quality preset, or set the exact CRF yourself.
  • Downscale to 1080p, 720p or 480p while converting.
  • Download every converted video at once as a zip archive.

How to use the Video Converter

  1. 1Drop in your videos, or click to choose them. You can add more at any time.
  2. 2Pick the target format. MP4 is the fast, plays-everywhere choice, WebM the open web format.
  3. 3Choose a quality preset, or switch to Custom and type a CRF. Optionally cap the resolution.
  4. 4Hit Convert and watch each file's progress. You can cancel a running batch.
  5. 5Download files one by one, or everything as a single zip.

Formats and codecs, honestly

Every conversion decodes the video and encodes it again, so converting between two lossy formats always costs a little quality. The CRF controls that trade-off: lower values keep more detail and make bigger files. The High preset is close to lossless to the eye, Balanced is the sensible default, and Small trades visible softness for real size savings. MP4 and MOV are written with a fast-start header, so they stream from the first byte.

The input side is wider than the output side: anything ffmpeg can read works, including AVI, MPEG-TS, FLV, 3GP and WMV sources.

Speed expectations

Encoding runs on ffmpeg compiled to WebAssembly, which downloads once (about 32 MB) on your first conversion. It is much slower than a native app: H.264 targets usually run at a fraction of real time, and VP9 for WebM is the slowest by far. Files convert one at a time, so a big batch simply works through the queue. Keep the tab open until it finishes.

Before and after converting

To cut a clip down before converting it, use the Video Trimmer. To shrink a file to a quality level or a target size rather than change its format, the Video Compressor is the better fit, and the Video to GIF Converter turns a short clip into an animated GIF. To check a file's codecs and streams first, run it through the Video Inspector.

Credits

Open source does the heavy lifting in this tool. Thank you to:

  • ffmpeg.wasm

    A WebAssembly build of FFmpeg, the audio and video toolkit behind half the media software you know.

Everything this site builds on is listed on the credits page.

Related tools

Frames to Video

Turn a series of images into a video. Drop in your frames, reorder them, set the frame rate and resolution, and encode the result as MP4 or WebM, ready to play anywhere.

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GIF to Video Converter

Convert an animated GIF into an MP4 or WebM video. Videos are far smaller than GIFs and play everywhere, so this is the quickest way to make a heavy GIF shareable.

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Subtitle Converter

Convert subtitles between SRT and VTT, shift their timing forward or backward, and fix frame rate drift to sync out-of-sync captions. Preview the parsed cues, catch format errors, and download the converted file.

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Video to Frames

Extract still frames from a video. Grab every frame, every Nth one or one per second, or step through and pick single frames by hand. Choose PNG, JPEG or WebP for the output and download everything as a zip.

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Video to GIF Converter

Turn a video clip into an animated GIF. Pick the exact section on a timeline, set the frame rate, size and loop behavior, and fine-tune the palette for a small file that still looks good.

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Audio Converter

Convert audio files between MP3, WAV, OGG, FLAC and M4A. Drop in as many files as you like, pick the target format and bitrate, and download the results one by one or all at once.

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