Buy Airtight — Private Portfolio Tracker: Your portfolio data never leaves your browser.

I built Airtight because I was tired of giving my entire trading history to startups that promise not to leak it — and then leak it anyway. Every portfolio tracker wants your email, your exchange API keys, your transaction history. Kubera charges $150/yr. Delta Pro charges $60/yr. CoinStats $48–120/yr. All of them upload your data to their servers. Airtight is the opposite of that. It's a single HTML file. You double-click it. You drop in your CSV exports from Binance, Coinbase, Kraken, Revolut, or any exchange. Your portfolio appears instantly — all calculated locally in your browser. **Here's the part I want you to verify yourself:** Open DevTools → Network tab. Import a file. Watch zero requests leave your machine. The only network calls are live price fetches — and even those happen directly from your browser, never through a server. There is no server. Technical decisions I made that some people will disagree with: - **No mobile app.** It's a file. It works in any browser including mobile. I'm not building an iOS app that phones home with your data. - **CSV exports, not API keys.** API keys are a security nightmare — one leak and someone drains your account. CSV exports are read-only and every exchange does them. - **No SaaS.** You download a file. You own it. I don't get to shut it down, change the pricing, or add tracking in an update. You can freeze any version. - **$49 one-time.** (20 dollars discount when paying with crypto). Not a subscription. I update it, you redownload it. What it handles: 8+ exchange formats (Binance, Coinbase, Kraken, Revolut, Gate.io, Bybit, KuCoin, Hyperliquid) plus a generic parser for anything that looks like a CSV. Excel files too. FIFO cost basis. Holdings dashboard. P&L. Charts. Dark theme. What it doesn't handle: futures (coming), tax reports (maybe), and your Coinbase login (intentionally). I genuinely want feedback — especially if an exchange CSV doesn't parse. Send it to me (sanitized) and I'll add a parser within 24 hours. That's the advantage of being a solo dev: I can ship fixes faster than any funded startup. — Ermis

Maker

📌

2mo ago

Hey everyone. Someone asked "can I try it first?" and honestly: fair.

So I added Airtight Free to the store. Same app — live prices, FIFO P&L, AES encryption — just manual entry capped at 50 transactions. No email wall, no trial expiration. Download it, open it, it works.

If you need CSV import from 70+ exchanges or unlimited trades, the full version's there at $29 (crypto launch discount). Same single HTML file, same zero-cloud guarantee.

→ airtight.sell.app