How do I play an H264 file?

VLC, MPV and PotPlayer play nearly every H264 file on desktop. Browser support varies: modern Chromium, Firefox and Safari play common containers via the HTML5 <video> tag, but niche H264 variants may fail. If a device refuses your H264, convert to MP4 with our H264 to MP4 converter for universal playback.

How do I play an MJPEG file?

VLC, MPV and PotPlayer play nearly every MJPEG file on desktop. Browser support varies: modern Chromium, Firefox and Safari play common containers via the HTML5 <video> tag, but niche MJPEG variants may fail. If a device refuses your MJPEG, convert to MP4 with our MJPEG to MP4 converter for universal playback.

H264 vs MJPEG — Differences, File Size & When to Use Each

H264 vs MJPEG

A detailed comparison of H.264 Raw Stream and Motion JPEG — file size, quality, compatibility, and which format to choose for your workflow.

Convert H264 → MJPEG Convert MJPEG → H264

H264

H.264 Raw Stream

Video Files

H.264 raw stream is an elementary bitstream containing only the video data encoded with the H.264/AVC codec without any container. It is commonly used as an intermediate format in video processing pipelines and for hardware encoder output.

About H264 files

MJPEG

Motion JPEG

Video Files

Motion JPEG (MJPEG) is a video format where each frame is independently compressed as a JPEG image. This intraframe-only approach enables easy frame-accurate editing and is widely used in security cameras and digital camera video modes.

About MJPEG files

Strengths Comparison

H264 Strengths

Universal hardware decode on every device since ~2010.
40-50% smaller than MPEG-2 at equal quality.
Mature ecosystem with dozens of encoders (x264 is the open-source gold standard).
Every browser, phone, TV, and car infotainment supports H.264.
Supports everything from 144p vertical phone video to 8K HDR masters.

MJPEG Strengths

Trivially simple — any JPEG decoder handles frames.
Every frame is a keyframe — instant seek and edit.
No inter-frame dependencies — recover from packet loss easily.
Hardware cost is minimal — any JPEG decoder works.
Lossless across edits — cutting and rejoining doesn't degrade quality.

Limitations

H264 Limitations

Patent-encumbered — encoding royalties apply for commercial use.
30-50% larger than H.265/AV1 at equivalent quality.
Raw .h264 bytestreams have no timecode — containers (MP4/MKV) add that.
High profiles decode slowly on pre-2010 hardware.

MJPEG Limitations

3-5× larger than MPEG-2; 8-10× larger than H.264 at comparable quality.
No audio — requires a separate track.
No standard container — appears inside AVI, MOV, MKV, MJPEG-over-HTTP.
Obsolete for mass-market delivery.

Technical Specifications

Specification	H264	MJPEG
MIME type	video/h264	video/x-motion-jpeg
Extensions	.h264, .264, .avc (raw bytestream)	—
Standard	ITU-T Rec. H.264 / ISO/IEC 14496-10 (AVC)	—
Typical containers	MP4, MKV, MOV, TS, FLV	AVI, MOV, MP4 (rare), raw stream
Profiles	Baseline, Main, High, High 10, High 4:2:2, High 4:4:4	—
Extension	—	.mjpeg, .mjpg
Frame format	—	Sequential JPEG (Baseline, usually 4:2:0)
Common in	—	IP security cameras, USB webcams, scientific imaging

Typical File Sizes

H264

1080p 30fps @ 5 Mbps (1 min) ~37 MB
4K 60fps @ 35 Mbps (1 min) ~260 MB
HD streaming (1 hour, 6 Mbps) ~2.7 GB

MJPEG

1-min VGA webcam clip 40-80 MB
1-min 1080p IP camera stream 300-500 MB
Canon DSLR 720p video (1 min) ~550 MB

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Convert between H264 and MJPEG online, free, and without installing anything. Encrypted upload, automatic deletion after 2 hours.

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Frequently Asked Questions

H264 (H.264 Raw Stream) is a video container format that bundles one or more video streams, audio tracks, and optional subtitles into a single file. The container format determines how metadata is organised and which codecs can live inside; the visual quality itself depends on the codec (H.264, H.265, VP9, AV1) rather than the H264 wrapper. It is part of the video files family.

MJPEG (Motion JPEG) is a video container format that bundles one or more video streams, audio tracks, and optional subtitles into a single file. The container format determines how metadata is organised and which codecs can live inside; the visual quality itself depends on the codec (H.264, H.265, VP9, AV1) rather than the MJPEG wrapper. It is part of the video files family.

VLC, MPV and PotPlayer play nearly every H264 file on desktop. Browser support varies: modern Chromium, Firefox and Safari play common containers via the HTML5 <video> tag, but niche H264 variants may fail. If a device refuses your H264, convert to MP4 with our H264 to MP4 converter for universal playback.

VLC, MPV and PotPlayer play nearly every MJPEG file on desktop. Browser support varies: modern Chromium, Firefox and Safari play common containers via the HTML5 <video> tag, but niche MJPEG variants may fail. If a device refuses your MJPEG, convert to MP4 with our MJPEG to MP4 converter for universal playback.

Upload your H264 to KaijuConverter and pick MP4, MOV, MKV, WebM, or any other target. Our pipeline uses FFmpeg under the hood and stream-copies when codecs are compatible (no quality loss) or transcodes at high-quality defaults otherwise. Conversion runs server-side; both files delete within two hours.

Only when the target requires re-encoding. If the codecs inside H264 match what the target container supports, FFmpeg stream-copies the streams and the output is bit-identical to the source. Transcoding uses transparent quality defaults (CRF 20–23 H.264) and produces output indistinguishable from the original at normal viewing distance.