01
Make vs move
Post Bridge
Post Bridge moves a finished file to many places.
Siren
Siren makes the file.
Compare
Siren vs Post Bridge
Post Bridge is a simple way for one person to publish to X, Instagram, LinkedIn, TikTok, YouTube and five more, with bulk video scheduling and an API and MCP for agents. Siren makes the video first, in your brand, then posts it.
The cut
Pick Post Bridge when you already have videos and want them on ten networks at once. Pick Siren when you need the video made.
At a glance
Where each product actually wins
Edge column is editorial judgment for a campaign team, not a feature scoreboard. Ties mean different jobs, not a coin flip.
| Dimension | Post Bridge | Siren | Edge |
|---|---|---|---|
| Primary job | Publish to many networks | Make brand videos and ad creatives, then post | Tie |
| Videos | Posts the videos you upload | Makes motion-graphics videos in your brand | Siren |
| Channels | 10 networks | X, LinkedIn, TikTok, YouTube | Them |
| Agent access | API and MCP on paid plans | API and MCP on every plan | Tie |
| Posting volume | Unlimited posts | One post per asset, credits per asset | Them |
| Starting price | $39/mo | $9.99 for one video, or Spark $19 a month (videos, MCP and API on every plan) | Siren |
Honest split
Pick the tool that matches the job
Premium products do not pretend to do everything. Neither do we.
Choose Post Bridge if…
- You already make your videos and need them everywhere.
- You post to many networks: Threads, Bluesky, Pinterest, Facebook, Google Business.
- Unlimited posts on one plan matter.
- Your agent should post files it already has.
Choose Siren if…
- You do not have the videos yet.
- You want product videos in your brand from one line.
- You want one video for $9.99 before any subscription.
- Your agent should ask for a video and post it in one go.
Mechanism
Four differences that matter in practice
02
Agents
Post Bridge
An agent can post through its MCP.
Siren
An agent can ask for the video and post it through Siren's MCP.
03
Reach
Post Bridge
Ten networks.
Siren
Four live networks, Instagram after Meta approves.
04
Using both
Post Bridge
Post Bridge can spread a video across ten networks.
Siren
Siren can make that video.
FAQ
Straight answers
Does Post Bridge make videos?
Not that we found in October 2026. It publishes the videos and images you give it.
Can I download Siren videos to post elsewhere?
Yes. Every video is an MP4 you can download and post anywhere.
Which is cheaper?
Post Bridge is $39 a month. Siren is $9.99 for one video, or $19 a month with videos included.
Also compare
Other tools people stack next to Siren
a thousand voices, one signature
Have nothing to cross-post yet?
Paste your site and Siren makes the first video.
