Your money. Every host. One dashboard.
Stop guessing what to charge sponsors. Defensible sponsor rates from cited public benchmarks, anchored to your real audience — synced live from Transistor, Buzzsprout, Podbean and Megaphone, with CSV import for every other host. AI-parsed inbound deals. Tax + cashflow forecasts that update with every transaction. Multi-currency invoicing in your sponsor's currency, not yours. We never connect to your bank — your money is your business.
The first 100 podcasters lock their rate for life.
CastMath is live. The financial layer your podcast has been missing is now running — episode P&L, sponsor rate calculator, tax forecasting, cashflow from confirmed deals. No bank connection required. No platform reading your revenue.
The first 100 podcasters to subscribe lock their current rate permanently. When pricing increases — and it will, as the feature set grows — Founding Podcasters pay what they paid on day one. Forever.
CastMath will also improve materially over the next 90 days based on what Founding Podcasters encounter in the field. If the rate calculator is missing your niche, if a tax jurisdiction needs adding, if something does not work as expected — tell us. Founding Podcaster feedback sets the build order.
Use the feedback button in the app
or email: hello@castmath.com
Your rate is locked. Your data stays yours. Your input ships.
Show me what my show is worth.
Pick your niche. Tell us your average downloads. We'll show you what to charge.
Three things every podcaster wastes time on.
You don't know what to charge sponsors.
So you guess. Or ask in Slack. Or copy a number from a 2019 blog post. Sponsor pushes back. You drop the rate. They sign. You suspect you left money on the table. You probably did.
Inbound sponsor emails get lost.
One sits unread for three weeks. One you replied to with the wrong rate. One had a perpetual-rights clause buried in paragraph five. There's no system between your inbox and your pipeline. Every deal starts cold.
Tax time is a panic.
Revenue is in five places. Costs are buried in your inbox. You build a spreadsheet from scratch every June. You miss deductions. You over-pay. You promise to do it differently next year. You don't.
CastMath does five things,
shipping today.
Sponsor Rate Calculator
Defensible rates from cited public benchmarks, anchored to your real audience. Connect your RSS, hook up Transistor or Buzzsprout for live download numbers, and CastMath quotes a mid-roll / pre-roll / sponsored-episode rate built from your top-quartile episode and the niche CPM range from Acast, AdvertiseCast, Adopter Media, IAB / PwC, and Magellan AI. Every rate quoted ships with the source.
- 145 cited benchmarks across 29 niches × 5 geos
- Auto-syncs downloads from Transistor, Buzzsprout, Podbean, Megaphone — CSV import for every other host
- Honest preview banner when you don't have enough data yet
AI surfaces that actually do work.
Four AI tools, all anchored to your real numbers — never generic LLM output. Every Asteris Grid call reasons from your benchmark, your audience size, your real ledger.
- Deal Advisor — paste a sponsor email, get a verdict (ACCEPT / COUNTER / WALK_AWAY) with red-flag clauses + draft reply
- Sponsor Inbox — forward inbound emails, AI extracts company / rate / format / term / exclusivity / payment, one click to promote
- Voice transactions — say "got two thousand from RetoolDB for a mid-roll on episode 142", drawer pre-fills the form
- Photo OCR — drop a receipt screenshot, payee + amount + date extracted
Episode P&L + sponsor pipeline.
Every dollar tagged to the episode that earned it. Every deal moves through a 9-stage pipeline. See profit per episode. See which formats pay. Move deals from LEAD to PAID without copy-paste.
- 9-stage pipeline: Lead → Qualified → Proposal → Negotiating → Agreed → Invoiced → Paid → Completed → Lost
- Auto-stamps agreedAt / paidAt as deals advance
- Inline transaction add / delete with tap-to-confirm
- Live media kit — public sponsor-facing URL with your numbers + rate card
Tax + cashflow that update with every transaction.
Country-aware, no surprises. Tax forecasts cover AU (GST + brackets + Medicare levy), US (federal + SE tax), UK (VAT + Class 4 NI). Cashflow projects the next 12 weeks weighted by deal-stage probability — never speculative numbers.
- Set-aside %: how much of every sponsor dollar to park
- Bracket-by-bracket breakdown of where your tax goes
- 12-week strip with stage probabilities (LEAD 5% → INVOICED 95%)
- Recurring costs (hosting, editing, software) sharpen the burn line
Sponsor-facing PDFs in two clicks.
Branded campaign reports for renewals. Multi-currency invoices in the deal's currency, not yours. Sequential invoice numbering across your whole account. Renewal tracker on the dashboard surfaces deals expiring inside 60 days.
- Sponsor Campaign Report PDF — three-page renewal pack, print → PDF → send
- Multi-currency invoicing — CM-YYYY-NNNN sequence, Net 30 or Net 60
- Renewal tracker — auto-fills due dates, dashboard surfaces 60-day horizon
- Email-forward inbox — sponsor inquiries arrive parsed, no paste step
We connect to your podcast host for download stats. That's it. No bank feeds, no Open Banking, no Plaid. Your money is your business — CastMath helps you record and understand it, never reaches in to grab it.
One product. One price.
Or half price, locked, if you're early.
Built by a Sydney studio,
for podcasters running a real business.
CastMath is built by Asteris — a small Sydney studio building tools for indie operators. Solo founder. AI-assisted build. Transparent roadmap.
We ship what we use. We listen to founding members. We charge fairly. The whole stack is on Cloudflare — Workers, D1, Email Workers — so the product feels fast wherever you are.
- STUDIO
- Built by Asteris
- FOUNDER
- Nick Lord
- BASE
- Sydney, AU
- STACK
- Cloudflare-native
- AI LAYER
- Asteris Grid
- STATUS
- Live since 2026-05
Things you'll
probably ask.
The product is live.
Lock founding pricing before it closes.
Start the 14-day trial. No card to start. If it doesn't pay for itself in your next sponsor conversation, leave.