Investor Guides

Learn the fundamentals of cost basis

Free, practical guides for retail investors on share price averaging, tax records, and portfolio psychology.

Fundamentals

Fundamentals

Weighted average vs simple average

Why the simple average shown by most brokers is misleading — and why WASP is the only figure that reflects your true cost basis.

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Strategy

Strategy

Averaging down: a practical guide

How to reduce your cost basis by buying more shares at lower prices — and the discipline required to do it without doubling down on a bad position.

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Strategy

Dollar-cost averaging explained

How investing a fixed amount on a regular schedule affects your weighted average price over time — including an honest look at when DCA underperforms.

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Tax & Records

Tax & Records

Cost basis and CGT in Australia

How the ATO calculates capital gains, why your WASP matters for tax records, and what you need to keep to stay compliant at tax time.

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Portfolio

Tracking multiple share positions

A practical system for maintaining accurate cost-basis records across multiple stocks — including how to handle partial sales and brokerage costs.

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Psychology

Psychology

The sunk cost fallacy in investing

Why your average purchase price should never determine whether you hold or sell — and how to make decisions based on future value, not past spending.

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Ready to calculate your WASP?

Free, instant, no sign-up required — works for any stock in any currency.

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