Replay the market.
Prove the strategy.
A professional backtesting workspace — bar-by-bar replay, simulated orders, Pine scripts and deep session analytics, all in your browser.
Free during the beta · No credit card · Your data exports anytime
Manual replay · Simulated trading · Pine scripts · Session analytics
The terminal
Everything you need to test and refine
One workspace from first replay to final report — no plugins, no rented widgets, no tab juggling.
Replay every bar
01Scrub to any point in history and step forward candle by candle, from 0.5× to 10×. Switch timeframes mid-replay — the tape never spoils future bars.
Trade directly on the chart
02Stretch a long or short position tool straight onto the candles — take-profit, stop-loss and R/R handles included, like every one of the 25+ drawing tools. P&L marks to market bar by bar as the replay walks.
22 chart types
03Candles, Heikin Ashi, Renko, Kagi, Point & Figure, Line break, Range — plus Volume Footprint and TPO that most platforms lock behind add-ons.
Pine scripts, in the browser
04Bring the indicator syntax you already know. Scripts transpile and execute client-side against the visible tape — edit, run, and see plots update instantly.
Multi-chart by design
05Split the workspace into synced panes — same symbol on two timeframes, or four markets side by side, with layouts that persist.
Alerts that fire in replay
06Price-cross alerts work against historical bars too — rehearse how you would have reacted, not just what you would have seen.
Never lose a session
07Projects group sessions, sessions record every trade and drawing, and the workspace auto-saves as you go. Close the tab, come back, keep testing.
Product tour
Inside the workspace
From the overview dashboard to a single replayed trade — every screen is built for the same question: is the edge real?
openbacktest
Net P&L
+$-725
Win rate
61.4%
Profit factor
2.21
Max drawdown
-4.8%
Cumulative net P&L
P&L calendar
Edge by hour
Evidence, not vibes
Turn every session into evidence
A strategy you can't measure is a story. Every replayed trade feeds a live statistical picture of your edge — when it works, when it bleeds, and whether it survives fees.
- Equity curve and underwater drawdown for every session
- P&L calendar plus hour-of-day and weekday edge maps
- MAE / MFE excursions and R-multiple distribution per trade
- One-click CSV export — your data is never hostage
Net P&L
Win rate
Profit factor
Max drawdown
Cumulative net P&L — real BTCUSDT tape
P&L calendar
Edge by weekday
The engine is ours
Most backtesters embed someone else's charts and bolt features around them. We built the renderer from scratch, so replay, orders and scripts are native to the chart — not layered on top.
Local-first speed
Replay stepping, order fills and Pine execution run in your browser. No round-trip per bar, no queue behind other users — the tape moves when you do.
Open to your stack
Sessions, trades and stats are reachable over a REST API with per-key scopes. Pipe results into your journal, dashboards, or research notebooks.
Python SDK and REST API
Automate your backtests with Python
Replay visually in the terminal, then automate the same workflow with the Python SDK. Every scripted session is synchronized back to the app with its trades and statistics.
- Python SDK for creating projects, sessions, and trades
- Sessions created by code appear in the terminal and dashboard
- REST API and scoped API keys for every other stack
- OpenAPI reference and Python guides in the documentation
From the beta cohort
Early traders, honest words
“Switching timeframes mid-replay without spoiling the forming candle is the thing I couldn't go back from.”
“I pasted my Pine indicator, hit Run, and it just drew. No exporter, no rewrite, no waiting on a server.”
“The calendar view told me in one glance that my Friday trades were paying for everyone else's mistakes.”
“Switching timeframes mid-replay without spoiling the forming candle is the thing I couldn't go back from.”
“I pasted my Pine indicator, hit Run, and it just drew. No exporter, no rewrite, no waiting on a server.”
“The calendar view told me in one glance that my Friday trades were paying for everyone else's mistakes.”
“Switching timeframes mid-replay without spoiling the forming candle is the thing I couldn't go back from.”
“I pasted my Pine indicator, hit Run, and it just drew. No exporter, no rewrite, no waiting on a server.”
“The calendar view told me in one glance that my Friday trades were paying for everyone else's mistakes.”
Pricing
Free today. Fair at launch.
The whole platform is free during the closed beta. When we launch, testing your strategy should still cost less than one bad trade.
Beta
$0while in closed beta
Everything unlocked while we polish the edges.
- Full terminal: replay, orders, Pine, alerts
- Projects, sessions and analytics
- Workspace auto-save and restore
- Feedback channel straight to the builders
Pro
at launch$19per month
For traders who test every day. Lock in early.
- Everything in Beta, kept unlocked
- Unlimited projects and sessions
- Developer API keys and exports
- Priority support
Partner
$12per seat / month
For mentors and desks who sponsor their traders.
- Organization with managed members
- Seats you fund, pooled on one invoice
- Pro included for the organization owner
- Admin controls and member insights
Billed through Polar · Cancel anytime · Beta feedback shapes the launch tiers
FAQ
Questions, answered
A browser-based backtesting workspace: replay historical markets bar by bar, place simulated orders with take-profit and stop-loss, run Pine scripts, and measure the results with session-level analytics.
Yes — during the closed beta everything is unlocked at no cost. At launch there will be a paid Pro tier; beta users will be the first to know and the last to be surprised.
No. Replay, orders, drawings and analytics are fully point-and-click. Pine scripting and the REST API are there when you want them, invisible when you don't.
Crypto pairs are live today with deep candle history across six timeframes. More asset classes are on the roadmap — the engine itself is market-agnostic.
Most alternatives rent their charting layer and build around its limits. We built the entire engine, so replay, order simulation, scripting and 22 chart types are native — and your subscription pays for testing, not third-party licenses.
Always. Every session exports to CSV in one click, and the REST API serves your sessions, trades and stats as JSON.
Your next strategy
deserves evidence.
Open the terminal, replay the tape, and let the numbers tell you if the edge is real.