An independent position-size reference for retail equity traders.

Why this site exists

The single most-cited cause of retail trading account blowups is over-sizing — taking positions large enough that a normal adverse move materially damages the account. The fixed-fractional rule (risk a small fixed percentage of capital per trade) is the most-tested defence. The arithmetic is trivial; the discipline of applying it consistently is not. tefinance.xyz exists to make the application frictionless.

The reviewer spent eight years on a sell-side equity research desk and now runs an independent equity-strategy practice. The methodology in this calculator is the same fixed-fractional framework he uses for client portfolio construction.

Editorial principles

• Risk-based sizing only. The calculator never sizes by share count or by dollar amount of position — only by dollar risk.
• Realistic risk percentages. Default 1 %; we do not encourage values above 5 % per trade.
• Named accountability. Marcus Chen, CFA, FRM, is the responsible reviewer. His CFA charter and FRM certification are verifiable through the CFA Institute and GARP public directories respectively.
• No commercial relationships. The site does not earn referral fees from any broker, platform, or trading-education service.
• Privacy by architecture. Trade levels and account size stay in your browser.

The team

tefinance.xyz is operated as a one-person editorial project alongside Marcus's equity-strategy practice. Marcus reviews every release of the calculator and every page of reference content before publication. He holds final editorial authority and is the named accountable person for every figure on the site.

Verification methodology

1. Math. Position-size formula is verified by inspection: shares = floor(account × risk_pct / |entry − stop|). Round-down ensures actual dollar risk never exceeds the budgeted amount.
2. Scenario simulation. P&L scenarios at multiple closing prices are linear extrapolations from entry, verified against manual calculations.
3. Edge cases. Stop = entry (zero per-share risk, returns null), stop > entry (short position, signed correctly), tiny risk percentages with small account size (verifies share-count flooring).
4. Locale rendering. Seven supported currencies render via Intl.NumberFormat('en-US').

What this site is not

• Not regulated investment advice. The calculator is a math tool. Specific equity recommendations require a regulated adviser.
• Not a trading platform. We do not execute trades, hold customer funds, or interface with any broker.
• Not a stock screener. We do not recommend names, levels, or timing.
• Not a tax-impact calculator. Capital gains tax, wash-sale rules, and short-vs-long-term distinctions are discussed on the tax page but not modelled in the calculator output.
• Not for derivatives. The calculator handles single-name equity. Options, futures, and CFD position sizing have additional considerations (notional vs. premium, margin requirements, leverage caps).

Get in touch

Calculation queries, scenario edge cases, content corrections, and partnership enquiries are all handled through the contact page. We commit to acknowledging every well-formed message within 24 business hours.