Video upload checker

How it works

1. 1

   Pick the platform

   Discord, WhatsApp, X, email, Instagram, TikTok, or Telegram.

2. 2

   Add your video

   The checker reads the file header locally: size, length, format, codec. Nothing uploads.

3. 3

   Fix what's flagged

   Every problem comes with a one-click fix that opens the right tool with the right setting.

Why videos fail to upload, and how the checker finds it

When an upload fails, platforms are famously unhelpful: a red toast, a generic error, or a silent spinner. Behind the message there are only a handful of real causes: the file is over the size limit, the video is longer than the platform allows, the container format isn't accepted, the codec inside can't be decoded, or the resolution is out of range. Each platform has different numbers for each rule, and none of them print the rule you broke.

This video upload checker applies those rules for you. It reads your file's header locally, in the browser: the actual size, the duration, the container (MP4, MOV, WebM, MKV, AVI), the video codec (H.264, HEVC, VP9, AV1), and even whether an MP4 is laid out for streaming. Then it compares every value against the published limits of the platform you picked and shows a plain verdict: what passes, what will bite you, and what is blocking the upload outright.

One-click fixes instead of guesswork

A diagnosis is only useful with a cure attached. Every failed check links straight into the tool that fixes it, preloaded with the right setting: too big for Discord opens the compressor at exactly 10 MB, too long for X opens the trimmer, an HEVC iPhone recording opens the H.264 converter, and a slow-to-preview MP4 opens the remuxer that fixes it in seconds without re-encoding.

All of those fixes run locally too. Your video is never uploaded, to this site or anywhere else, at any point in the process, which is why the checker works instantly even on multi-gigabyte files.

Why nothing uploads

Other tools send your video to their servers, which costs them money per file, so they add watermarks, cap file sizes, and make you sign up. This tool does the work right here in your browser using your own device. Your file is never uploaded, so there is no wait, no watermark, no size limit, and no account.

Questions

Why won't my video upload to Discord?

Almost always file size: Discord caps uploads at 10 MB without Nitro. The checker confirms it in one look and the fix button opens the compressor preset to exactly 10 MB. If the file fits but shows no preview, the codec is usually the culprit, often HEVC from an iPhone.

Why won't my video send on WhatsApp?

WhatsApp accepts big files but re-compresses anything over roughly 16 MB, hard, and rejects some formats outright. The checker tells you which case you're in and whether compressing or converting is the right fix.

Why does my video fail to upload to X (Twitter)?

X requires H.264 MP4 or MOV, under 512 MB and under 2 minutes 20 seconds for standard accounts. The checker tests all three against your file and links the trimmer, the compressor, or the converter accordingly.

Why is my video attachment too big for email?

Gmail caps attachments at 25 MB and Outlook at 20 MB, so a 22 MB video sends from one and bounces from the other. The checker warns about exactly this band and links the compressor with an email-sized target.

My video uploads but plays as a black screen or won't preview. Why?

That is a codec problem, not a size problem: the platform accepted the container but can't decode the video inside it, typically HEVC (H.265) or AV1 on an older device. The fix is re-encoding to H.264, which the converter does in one step.

Does the checker upload my video to test it?

No, and that is the point: it reads a few kilobytes of the file's header in your browser to identify the format and codec, checks the numbers against the platform's documented limits, and never sends anything anywhere.

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