Eleven platforms · one composer · $5 an account
Write the post once, land it everywhere it belongs
One caption in, a tailored version out to each platform you connected — trimmed for X, titled for YouTube, formatted for LinkedIn. Scheduled or right now.
Official APIs · No passwords · Cancel any time
One caption, a card per platform
X trims to 280, YouTube takes a title, LinkedIn keeps your line breaks. Edit any card without touching the others.
Queue and calendar
Set your slots once; "add to queue" fills the next free one. The month at a glance, colour by status.
Bulk upload and recycling
Drop a folder of clips or a CSV, spread them across slots. Evergreen posts repeat on a schedule you set.
Post from Claude or code
A REST API and an MCP server on one key, included. "Post this clip to Reels and Shorts at nine" — done.
How it works
From one caption to every feed you own
Write it once
One composer, one caption, your media. Pick which of your connected accounts it goes to.
Tailor it per platform
Each platform gets its own card: X trims to 280, YouTube takes a title, LinkedIn keeps your line breaks. Edit any card without touching the others.
Post now or schedule
Publish immediately, pick a time, or drop it in the queue. Every target reports back with a link to the live post — or the reason it failed.
The composer
One caption, eleven honest versions
Every platform has its own limits and its own habits. Instead of one lowest-common-denominator caption, the composer keeps a card per target. The shared text fills them all; you fix the ones that need fixing. The counter on each card is the platform's real limit, counted the way the platform counts.
Try the composerCaption
Three things I got wrong about lighting a talking-head video — and the $40 fix for each. Full breakdown ↓
3 lighting mistakes (and the $40 fix for each)
Description: shared caption
Shared caption, line breaks kept.
Needs media — attach the video or a frame.
What you are buying
A scheduler that says exactly what it does
Your own authorisation, every time
You sign in to each platform yourself. We hold a token the platform issued, never your password, and you can revoke it from the platform side at any moment.
Official APIs only
Nothing here automates a browser or pretends to be you. Every post goes through the platform’s published API, which is also why some formats are not possible — we say so on the card rather than faking it.
Priced by what you connect
Two accounts is ten dollars. Eleven accounts is fifty-five. There is no plan to outgrow and no seat to buy; disconnect an account and its charge stops with the next invoice.
What it will not do
It will not get you followers, engagement or reach. It puts the post you wrote where you told it to, at the time you said. The rest is the post.
Everything in it
The scheduler, one line each
No feature tiers: every workspace has all of it, from the first account.
Queue slots
Set the days and times once; "add to queue" fills the next free slot.
Calendar
The month at a glance, colour by status, click a day to start a post there.
Bulk upload
Drop a folder of clips or a CSV; spread them across slots or one a day.
Threads
Extra parts become a thread on X, Threads and Bluesky — the caption is post one.
First comment
Hashtags or a link, posted right after publishing on Instagram, LinkedIn, YouTube, Threads.
Recycling
Repost every few weeks, up to a count you set — evergreen without the calendar work.
Fitted media
An image outside a platform's ratio is padded with a blurred copy of itself. No white bars.
Carousels & documents
Several images where the platform allows, a PDF as a LinkedIn document.
Analytics
Impressions, likes, comments, saves per post — and the hours your posts do best.
API & MCP
Post from your code or from Claude, Cursor, ChatGPT. One key, included.
Price
$5 per connected account / month
Connect two accounts, pay ten dollars. Connect eleven, pay fifty-five. Unlimited posts, every feature, on every plan — because there is only one plan.
No trial without a card, no card without a price
You see the total for your accounts before you pay a cent.
One post, written once — every platform gets its own version.
Trimmed for X, titled for YouTube, fitted for Instagram, queued for the slot you chose. You write; the composer does the eleven-way translation.
API & agents
Post from your code, or from Claude
One key opens a REST API and an MCP server. Tell Claude Code, Cursor or ChatGPT "post this clip to TikTok, Reels and Shorts tomorrow at nine" and it does — with the same per-platform rules the composer enforces. Included, no add-on.
Read the docsclaude mcp add --transport http castacross \ https://castacross.com/mcp \ --header "Authorization: Bearer cp_…" > post the clip in ~/Desktop/lighting.mp4 to tiktok, instagram and youtube shorts, caption "3 lighting mistakes", tomorrow 9am
Free tools
Small things you check before you post
Instagram username checker
Is the handle taken? Live check, no login, plus the rules a name has to meet.
Character counter
One paste against eleven platform limits, counted the way each platform counts.
Social media image sizes
Every size from the platform's own page, with a cropper that exports the exact pixels.
Instagram fonts generator
20 copy-paste text styles for your bio and name — bold, italic, script, gothic, bubble.
YouTube money calculator
What views earn from your own RPM range — the number Studio reports, not a made-up rate.
Username generator
Handle ideas from your own words, within each platform's rules — check any of them in a click.
Guides
Answers from the source, dated
How much does YouTube pay per 1,000 views?
There is no fixed rate. What YouTube actually promises — the revenue share, the Shorts creator pool, the eligibility bar — and why two channels with the same views earn different money.
Checked 2026-08-29
How to see your YouTube subscribers
Where the list lives in YouTube Studio, why it only shows some of them, and why a subscriber can be real and still invisible to you.
Checked 2026-08-29
When does YouTube start paying you?
The four thresholds between joining the Partner Program and the first deposit, the monthly calendar Google actually runs on, and why the first payment usually lands a month later than people expect.
Checked 2026-08-29
Questions
Which platforms can I post to? +
Instagram, TikTok, YouTube, X, LinkedIn, Threads, Bluesky, Pinterest, Reddit, Facebook Pages and Google Business. You connect each account with its own sign-in; you can connect several accounts on the same platform.
How much does it cost? +
$5 per connected account / month, billed monthly. There are no tiers, no seats and no per-post charges on the eleven platforms above.
Do you need my passwords? +
No. Each platform asks you to authorise access on its own site and hands us a token scoped to publishing. We never see or store a password, and you can revoke the token in the platform’s settings.
Can I edit the caption per platform? +
Yes. The composer shows one card per target. The shared caption fills every card; change any card and only that platform gets the change.
What happens when a post fails? +
The target shows the platform’s error next to it and a retry button. Failures on one platform never hold back the others.
Can I cancel any time? +
Yes, from your account page in two clicks. Your access runs to the end of the period you paid for; see the refunds page for the exact terms.