View Media Info Online — See a Video or Audio File's Codec, Resolution & Bitrate

How it works

Check your video specs in seconds, with no software

You downloaded a file and your player refuses to open it, or it stutters, or it has no sound. You want to know why before you go hunting for a converter: is the video HEVC that your player can't decode, is the audio a codec nobody supports, is the resolution 4K that your old laptop chokes on, or is the bitrate just too high for smooth streaming? This tool lets you view media info online with nothing but the browser. Drop an .mp4, .mkv, .mov, .avi or an .mp3/.wav, and within moments you can see exactly what is inside it — the container, the codecs, the resolution, the frame rate and the bitrate. It is the fastest way to check video codec or check video resolution online without installing MediaInfo, ffprobe or any desktop program, and without uploading a private file to a random website.

Two levels of detail: quick info, then a deep scan

A browser can read some facts about a media file on its own — how long it is, how big the picture is, what type the file claims to be. It cannot see the codec name, the bitrate or the audio sample rate, because those live inside the encoded stream and the browser only decodes what it recognizes. So this tool gives you two layers:

Quick info (instant)

Read straight from the file on your device the moment you drop it: file name, file size, MIME type, an estimated container (from the file extension), duration, and for video the resolution and aspect ratio. This needs no download and works offline.

Deep scan (one click)

Click Run deep scan and the tool loads the FFmpeg WebAssembly engine — the same engine the command-line tool ffprobe uses — and probes every stream the way a desktop media inspector does. You get the exact container format, the overall bitrate, and for each stream the codec, profile, resolution, frame rate, pixel format, bitrate, sample rate, channel layout, subtitle format and language tag. The deep scan is the part that answers "what codec is this" and "why won't it play".

Container vs. codec: what the report actually means

Two terms trip people up, and understanding them is the whole point of a media-info tool.

The container is the box

The container — MP4, MKV, MOV, AVI, WebM — is the wrapper that holds one or more streams together with timing information. The extension tells you the box. A single container can hold wildly different video and audio inside it, which is why two .mp4 files can behave completely differently.

The codec is the recipe

The codec — H.264, HEVC/H.265, VP9, AV1 for video; AAC, MP3, AC3, Opus, FLAC for audio — is the method used to compress each stream. A player must understand both the container and every codec inside it. When a file "won't play", it is almost always a codec the player lacks (for example HEVC in some browsers, or DTS audio), not the container. The deep scan names the codec so you know exactly which one is the problem, and the related tools on this site can then transcode that one stream into something universal.

What the tool reports, field by field

File

File name, size in KB/MB/GB, and the MIME type reported by the browser. These are the basics you need when comparing two exports or checking whether a download finished.

Container

The wrapper format. Quick info estimates it from the extension; the deep scan reads the real format tag FFmpeg finds inside the file, which is more reliable when an extension is wrong or missing.

Video stream

Codec and profile (for example H.264 High), resolution such as 1920×1080, frame rate (23.976, 25, 30, 59.94 fps), pixel format (yuv420p and friends), and the video bitrate in kb/s. This is what tells you whether a clip is 4K, whether it is 60 fps, and how heavily it is compressed.

Audio stream

Codec and profile (AAC LC, AC3, Opus and so on), sample rate (48000 Hz, 44100 Hz), channel layout (mono, stereo, 5.1) and audio bitrate. This is where you find out why a file has no sound in a player, or why dialogue is quieter than the music.

Subtitle and data streams

Any embedded subtitle tracks (SRT, ASS, VobSub, PGS) and their language, plus attachment or data streams. Handy when a file "has subtitles" that your player ignores.

Browser inspector vs. desktop MediaInfo vs. an upload site

A media-info tool can be a web page, a desktop program, or a server you upload to. The table shows where each one wins.

Common scenarios for inspecting media info

A file will not play in your player

QuickTime opens the .mkv but shows no video, or VLC plays sound but no picture. Run the deep scan: the codec line tells you the video is HEVC or the audio is DTS — codecs your target player lacks. Now you know precisely what to transcode, instead of guessing.

You need to know the resolution and frame rate

You recorded or received a clip and need to confirm it is 1080p at 30 fps (or 4K at 60) before you upload it somewhere with size limits. The quick info shows resolution instantly; the deep scan confirms the exact frame rate so you don't waste a long upload on the wrong spec.

You want to check the bitrate before streaming

A high bitrate makes a file look great but stutter over a slow connection. The deep scan reports the video and audio bitrates in kb/s, so you can decide whether to compress it (the related compressor on this site does that in-browser) before sharing.

You received audio with no sound

The deep scan lists the audio codec, sample rate and channels. If it shows AC3 or DTS where your player expects AAC, that is your answer — and the converter can remux or re-encode the audio into something universal.

You are comparing two exports

Two MP4s of the same scene, one twice the size of the other. The bitrate and codec columns show you exactly why — one is H.264 at a higher CRF, the other HEVC — so you can pick the efficient one without eyeballing quality.

Supported formats in detail

The checker accepts the same broad set of containers the rest of this tool cluster handles. Video: MP4, M4V, MKV, MOV, AVI, WebM, MPEG-TS/M2TS, FLV, OGV, 3GP, VOB, WMV, RMVB, DIVX, MPG/MPEG and more. Audio: MP3, WAV, M4A, AAC, FLAC, OGG/Opus, CAF, AIFF, AC3, EAC3, DTS and similar. The quick info handles anything the browser recognizes; the deep scan, built on FFmpeg, can parse files the browser itself cannot even decode — which is exactly why it is worth the one-time engine download when you hit an unusual file. The output report is plain text, so you can paste it into a bug report, a support ticket or your notes without any special viewer.

Privacy: your file never leaves your device

Every step happens inside your browser tab. When you open a file, the browser reads it into memory; the quick info is taken from that in-memory copy with no extra work at all. The deep scan loads the FFmpeg engine as WebAssembly and probes the file on your CPU. The only network traffic is the page itself, plus a one-time download of the FFmpeg engine (about 30 MB) the first time you run a deep scan; after that it is cached by your browser. No request carrying your file content ever reaches our servers, and there is nothing for us to store or delete. You can even disconnect from the internet after the page loads and the tool still works.

Frequently asked questions

Troubleshooting: when the info looks wrong

The quick info shows the wrong container

Quick info guesses the container from the file extension. If a file was renamed or has no extension, that guess can be off. Run the deep scan — it reads the real format tag from inside the file, which is authoritative.

The deep scan says it could not read the streams

The file may be truncated, encrypted, or in a format this engine build does not support. The quick info is still valid. Try the related player to see if the browser can decode it at all; if not, a desktop converter is the more reliable next step.

The duration or resolution is missing

Some exotic or streaming-oriented containers do not advertise duration until fully parsed, and a codec the browser can't decode yields no resolution. The deep scan reports whatever FFmpeg finds; if a value is absent, the stream likely omits it (common with live captures).

The audio shows but the video does not

The video codec is probably one your browser's media element can't decode, so quick info has no resolution for it. The deep scan reads the video codec and resolution directly from FFmpeg regardless, so run it to see the full picture.

When to use desktop software instead

The online checker is ideal for a one-off look: you were sent a file that misbehaves, you need to confirm a resolution before uploading, or you want to know a codec without installing anything. It intentionally keeps things simple — one file, a quick read, an optional deep scan, and a copyable report.

If inspecting media is part of your routine — checking folders of episodes, auditing a library for 4K/HEVC, or needing to act on what you find (transcode, remux, compress, extract) in bulk — a desktop app is the better fit. Total Video Converter for Mac uses your Mac's hardware encoders, handles queues of files, and writes to any format you need, while Total Video Player Pro plays and manages large libraries and reports codec and track info on the fly during playback. That is exactly what this free tool is here to point you towards.