# ForexFin

> Free forex calculators and price alerts for retail traders. No signup, no tracking. Math runs in your browser; alerts run on a server you don't own.

## About
ForexFin is a focused set of single-purpose tools for active retail forex traders. Every calculator is a single self-contained page; live ECB rates are used where currency conversion matters, but no per-page broker integration. The alerts engine is a small server-side feature that watches a quote stream and pings on threshold or pattern hits, with conservative defaults so it doesn't double as a notification spam pipe.

The framing is "retail trader who knows what they're doing." No tutorials disguised as funnels. The "learn" pages exist for genuine quick reference, not lead capture.

## Calculators
- [Position Size](https://forexfin.tech/calc/position-size/): lots from balance × risk % × stop-loss pips with cross-currency conversion.
- [Pip Value](https://forexfin.tech/calc/pip-value/): pip value in account currency for any pair and lot size.
- [Margin](https://forexfin.tech/calc/margin/): required margin from leverage, lot size, and pair.
- [Swap](https://forexfin.tech/calc/swap/): overnight swap cost/credit from triple-swap day and broker rate.
- [Risk-Reward](https://forexfin.tech/calc/rr/): R:R ratio plus expected value at a given win-rate.
- [Kelly Criterion](https://forexfin.tech/calc/kelly/): optimal position fraction for a given edge.
- [Spread Cost](https://forexfin.tech/calc/spread-cost/): round-trip spread cost in account currency.
- [Trade Plan Builder](https://forexfin.tech/calc/trade-plan/): combines position size, R:R, and exit ladder into a printable plan.

## Reference visualizers
- [Currency Correlation Matrix](https://forexfin.tech/correlation/): rolling-window pair correlations.
- [Currency Strength Meter](https://forexfin.tech/currency-strength/): cross-pair-derived strength per currency.
- [Market Hours Visualizer](https://forexfin.tech/market-hours/): four-session overlap visualizer (Sydney, Tokyo, London, New York).

## Methodology & data
- [The Mathematics of Retail Risk Management](https://forexfin.tech/methodology/): the exact formula behind every calculator — position sizing, pip value (incl. JPY), margin, margin-level/stop-out, risk:reward, the Kelly criterion adjusted for forex leverage, swap, spread cost, currency strength, and pair correlation — each with a worked example.
- [Data & Methodology Documentation](https://forexfin.tech/docs/): data sources (ECB reference rates, Financial Modeling Prep, CFTC), refresh cadence per surface, the data structures behind each tool, the spread-cost algorithm, and as-of/freshness conventions.
- [Weekly G8 Strength & Volatility Reports](https://forexfin.tech/reports/): a dated, permanent archive of relative currency strength and realized volatility for the eight major currencies, computed from daily closes. Each weekly edition (e.g. /reports/2026-W23/) is a citable data table; settled weeks are immutable.

## Macro context
- [DXY Dollar Index (synthetic, live)](https://forexfin.tech/macro/dxy/): live US Dollar Index synthesized from its six ICE-standard component currency pairs (EUR, JPY, GBP, CAD, SEK, CHF). Per-component contribution breakdown, 90-day daily history, and the public formula.
- [Gold Price (XAU/USD, live)](https://forexfin.tech/macro/gold/): live gold spot price per troy ounce with day change, 50/200-day moving averages, and 90-day history, framed for dollar and risk positioning.
- [Oil Price (Brent crude, live)](https://forexfin.tech/macro/oil/): live Brent crude price per barrel with day change, moving averages, and 90-day history, framed for the commodity currencies (CAD, NOK). Benchmark is Brent, not WTI.
- [US Treasury Yield Curve (daily)](https://forexfin.tech/macro/yields/): the full US Treasury curve (1-month to 30-year), updated daily, with the 2s10s spread and 10-year trend, framed as the interest-rate backdrop for USD pairs.
- [Economic Calendar (weekly, FX-relevant)](https://forexfin.tech/macro/calendar/): high- and medium-impact scheduled releases for the major FX currencies for the current week, with times in UTC, estimates, and prior readings.
- [COT Positioning (weekly)](https://forexfin.tech/macro/cot/): large-speculator (non-commercial) net positioning in the major CME currency futures (EUR, JPY, GBP, CHF, CAD, AUD, NZD) from the CFTC's weekly Commitments of Traders report, with weekly change and % of open interest. Public-domain CFTC data.

## Learn
- [What is Leverage](https://forexfin.tech/learn/leverage/)
- [What is a Pip](https://forexfin.tech/learn/pip/)
- [Margin Call Mechanics](https://forexfin.tech/learn/margin-call/)

## Alerts (paid)
- [Price Alerts](https://forexfin.tech/alerts/): server-side alerts on level/cross/divergence with email + webhook delivery.

## Operator
Solo-built and solo-run by Constantin R. T. Also operates: [duerelay.com](https://duerelay.com), [billnode.app](https://billnode.app), [sellingcurrently.com](https://sellingcurrently.com), and others under the [Constantin Works](https://constantin-works.com) portfolio.

## Contact
hello@forexfin.tech