Substack Video Converter — Free Online MP4 Converter 2026

Updated: March 2026

Need to grab a video off Substack and turn it into an MP4 or MP3? You’re in the right place. OnlineVideoConvert.net makes it easy, free, and incredibly fast. I hate bloated software and mandatory sign-ups, so we built this to work without any of that. Just paste your Substack URL, pick a format, and you’re done in seconds. It works perfectly on your phone, tablet, or laptop—no matter what browser you use.

How to Convert in 3 Steps

1. Copy the URL — Go to Substack, find your video and copy its link
2. Paste & Choose Format — Paste the URL above and select your output format (MP4, MP3, WebM…)
3. Convert & Download — Click Convert and save the file to your device

Why Use OnlineVideoConvert.net for Substack?

I know there are a ton of converters out there, but most of them are… well, frustrating. They’re either slow or they lock the best features behind a paywall. Here is how we stack up against the rest:

We handle thousands of Substack conversions every single day. Most finish in under 15 seconds because we don’t believe in making you wait around.

Supported Output Formats

Curious about what you can actually download? Here is the full list of formats we support for Substack content:

Video Formats

• MP4 — The king of compatibility. It plays on literally everything. If you aren’t sure what to pick, choose this.
• WebM — Perfect for the web. These files are usually smaller and great for embedding.
• AVI — An old-school format that still works great with legacy players and editing tools.
• MOV — If you’re an Apple user working in iMovie or Final Cut, this is your friend.
• MKV — A powerful container that can handle multiple audio tracks and subtitles easily.
• FLV — Flash video. A bit dated, but still necessary for some older apps.
• WMV — The standard Windows format, which is still a solid choice for PowerPoint presentations.

Audio Formats

• MP3 — You can’t go wrong here. It’s the universal standard for music and voice clips.
• WAV — This is uncompressed, lossless audio. It sounds amazing but the files are huge.
• AAC — This offers better compression than MP3 and is the native choice for Apple devices.
• OGG — A great open-source format that web developers and Linux fans love.
• FLAC — Audiophile-grade quality. It’s lossless but manages to keep the file size reasonable.
• M4A — A clean, high-quality option that’s perfect for podcasts and voice notes.

Is It Safe and Legal to Convert Substack Videos?

Let’s be totally upfront about this.

Safety: We handle everything on our own servers, so you don’t have to install anything sketchy on your device. We use HTTPS encryption, we don’t track your personal info, and we automatically wipe your converted files from our system after 2 hours. Your privacy isn’t just an afterthought here.

Legality: Generally speaking, converting public Substack videos for your own personal, offline use falls under fair use in most places. But don’t be that person—don’t go redistributing copyrighted work or trying to sell someone else’s content. Use the tool responsibly and respect the people who actually made the videos.

Frequently Asked Questions

What’s the best format to convert Substack videos to?

Usually, MP4 is the winner for video because it works everywhere. If you just want the audio, go with an MP3 at 192kbps. If you’re a total audio nerd and want the highest quality possible, go for FLAC or WAV.

Can I convert Substack videos on my phone?

Absolutely. The site is fully mobile-optimized. Whether you’re on an iPhone using Safari or an Android using Chrome, the experience is fast and smooth. No app store downloads required.

Is the Substack video conversion actually free?

Yes, 100%. No “premium” versions, no daily limits, and no hidden fees. We keep the lights on with a few small ads so we don’t have to charge you a dime.

How long does the conversion take?

Most Substack videos are ready in about 5 to 15 seconds. If you’re just extracting audio, it’s even faster—usually under 5 seconds.

Do I need to create an account?

Nope. I hate signing up for things just to use a simple tool. You don’t need to give us your email or create a password. Just show up and start converting.

What if my Substack link doesn’t work?

Double-check that the video is public. If the post is behind a paywall or has been deleted, our converter won’t be able to reach it. Also, make sure you’ve copied the full URL from your browser.

Ready to get started? Paste your URL into the box above and you’ll have your file in no time. We also support over 40 other platforms including YouTube, TikTok, and Twitter, so feel free to bookmark us!