Bitcoin dollar cost averaging backtest calculator (AUD)
Run a Bitcoin AUD dollar-cost-averaging backtest from any start month between January 2014 and last month. Set your contribution amount and frequency (monthly, fortnightly, weekly) and see total invested, BTC accumulated, current portfolio value, total return, annualised money-weighted return (IRR), and optional ATO capital gains tax if you sold the whole position today. AUD-native (most equivalent backtests online use USD). Auto-updated on every site refresh.
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Portfolio value over time
CGT estimate if sold today
What is dollar cost averaging?
Dollar cost averaging is the practice of buying a fixed AUD amount of an asset on a fixed schedule, regardless of the price at the moment of purchase. For example, $200 every fortnight, automatically, for as long as the strategy runs.
The mechanic is that the fixed AUD amount buys more units when the price is low and fewer units when the price is high. Averaged across many purchases, your effective entry price is the weighted average of every buy. The strategy removes the question "is now the right time to buy?" because the answer is always "yes, today is one of the scheduled buy days".
The framework was popularised for equity index investing in the 1990s and has carried over to Bitcoin since at least 2017. It is the strategy used by automated buy programs at Australian exchanges (CoinSpot's Recurring Buys, Independent Reserve's Auto-Invest, Swyftx's Recurring Orders, Binance Australia's Auto-Invest), by Bitcoin-only services like Swan Bitcoin or River, and by self-directed investors using manual cadence.
DCA trades against two alternative strategies:
- Lump-sum investing deploys all available capital at once. Outperforms DCA in a sustained uptrend (because all your capital is exposed earlier) but underperforms in a sustained downtrend (because you bought the top with all of it).
- Discretionary timing buys at moments judged to be favourable (cycle bottoms, dips, oversold signals). Outperforms DCA when the timing calls are right but underperforms when they are wrong, and most retail traders historically demonstrate net-negative timing skill versus a mechanical DCA baseline.
DCA is the conservative middle ground. It does not maximise expected return in any single sample path; it minimises regret across the distribution of possible paths.
Why IRR matters more than total return
Total return is the headline number that gets quoted. It is also misleading for any strategy that adds capital over time. Total return treats every dollar invested as equivalent, regardless of when the dollar arrived in the position.
Consider a $100 monthly DCA started in January 2017 and held to December 2025. Total invested is $10,800 (108 months at $100). If the current value is $54,000, the total return is 400 percent. That sounds excellent. But the average dollar in that strategy was invested for only about 54 months (4.5 years), not the full 108 months. To grow an average dollar by 400 percent in 4.5 years requires an annualised return well above the 4.5-year compound rate of a single lump-sum invested at the start.
The honest metric is internal rate of return (IRR), specifically the money-weighted variant. IRR is the constant annual rate that would discount the timing-adjusted cashflows to zero. For DCA, IRR weighs early contributions more (longer compounding window) than late contributions (shorter window), producing the rate that correctly reflects the actual compounding the strategy generated.
The two numbers shown in this calculator:
- Total return percentage. (final value minus total invested) divided by total invested. The headline number that ignores timing.
- Annualised IRR. The money-weighted compound annual return. The honest comparison metric for any strategy that contributes over time. Computed via Newton's method on the monthly cashflow series.
When comparing DCA to a benchmark (lump-sum, ASX 200, term deposit), always use IRR. Comparing total returns across strategies with different contribution timings is meaningless.
CGT treatment in Australia
When you dispose of Bitcoin in Australia (sell it for AUD, swap for another crypto, gift it, or use it to pay for goods or services), the ATO treats it as a CGT event. The capital gain is the AUD disposal proceeds minus the AUD cost base of that parcel. The cost base is what you paid in AUD for that specific parcel of BTC.
For a DCA strategy, every contribution creates a separate parcel with its own cost base and acquisition date. When you sell some BTC, the ATO requires you to identify which parcels you sold (FIFO, LIFO, or specific identification all permitted, with consistent application). The CGT calculation then runs parcel-by-parcel: each parcel sold produces its own gain or loss, with the 50 percent discount under section 115-25 applying only to parcels held more than 12 months.
The CGT estimate in this calculator simplifies the parcel logic. It treats the entire DCA position as a single composite asset:
- Total cost base equals total AUD invested across all contributions.
- Total proceeds equals current portfolio value (BTC accumulated times today's AUD price).
- Gross capital gain is the difference.
- 50 percent discount applies if the first contribution is at least 12 months ago (which is the case for any backtest with 13 or more contributions). In reality, parcels under 12 months would not qualify; the simplified estimate slightly overstates the discount.
- CGT payable is the post-discount gain times your marginal tax rate.
For a precise parcel-by-parcel CGT calculation on a real disposal, use the Crypto CGT Calculator (single disposal) or crypto tax software like Summ, Syla, or Koinly (full-year report). For SMSF disposals, the rate is 15 percent in accumulation and 0 percent in pension phase, with a one-third (not 50 percent) discount on 12-month-plus parcels; use the SMSF Crypto CGT Calculator.
Methodology
- Data source. Public market-data endpoint, vs_currency equals AUD, daily prices downsampled to monthly closes. Refetched on every site build.
- Frequency conversion. Fortnightly amount becomes (amount × 26 / 12) monthly equivalent. Weekly becomes (amount × 52 / 12) monthly. The simulation runs on a monthly cadence with the adjusted monthly amount. Total invested across the period equals the user-supplied amount × purchases per year × years held.
- BTC accumulated. For each month from the start to the latest available, BTC purchased equals (monthly equivalent amount) divided by (month's AUD close). BTC totals across all months.
- Portfolio value. Cumulative BTC times the most recent month's AUD close.
- Total return. (Portfolio value minus total invested) divided by total invested, times 100.
- Annualised IRR. Newton's method on the monthly cashflow series: each month has a negative cashflow (the contribution) plus a final positive cashflow (the portfolio value) at the last month. Solve for monthly rate r such that NPV equals zero, then annualise via (1 + r)^12 - 1.
- CGT. Gross gain equals (portfolio value minus total invested). 50 percent discount applies when the first contribution is at least 12 months ago. Tax equals (gross gain minus discount) times marginal rate divided by 100.
Limitations
- Monthly cadence simulation. Fortnightly and weekly frequencies are simulated on a monthly cadence at the monthly close. This understates intra-month volatility capture (a real weekly DCA strategy benefits from averaging across the monthly range, not just buying at the close). The total invested and approximate BTC accumulated match reality closely; the precise BTC per contribution differs.
- No fees, no slippage, no spread. Real exchange purchases incur a maker or taker fee (CoinSpot Recurring Buys: 1.0 percent default, Independent Reserve: 0.5 percent, Binance Australia spot: 0.1 percent). Real prices include a spread above the index price. The backtest uses raw index prices with no friction. For a realistic adjustment, deduct 0.5 to 1.0 percent of total invested as cumulative friction.
- Composite-asset CGT simplification. The CGT estimate treats the entire position as one parcel. In reality, parcels under 12 months at the disposal date do not qualify for the 50 percent discount. The simplified estimate slightly overstates the discount for any DCA strategy with recent contributions.
- Historical-only backtest. The calculator shows what would have happened given past prices. Future Bitcoin returns can differ substantially. The historical IRR of any DCA window ending in late 2021 or April 2024 is much higher than any window ending in a cycle bottom.
- AUD price data is monthly close, not daily mean. Bitcoin moves intramonth; the close is one point in time. Strategies that buy at month-open or mid-month would have slightly different effective entry prices. For a 5+ year backtest this is a small effect; for a 1-year backtest it can matter.
Related tools
- Bitcoin Logarithmic Regression Bands (AUD) - long-run fair value and ±σ bands. Useful for understanding where the backtest end-point sits in cycle context.
- Bitcoin Halving Countdown + Cycle Overlay - compare your DCA window against the historical halving cycle pattern.
- Crypto CGT Calculator - parcel-by-parcel CGT for a real disposal of a single parcel.
- SMSF Crypto CGT Calculator - 15 percent accumulation, 0 percent pension, one-third discount.
- Tax-Loss Harvesting Calculator - estimate EOFY tax savings from realising losses in a DCA position drawdown.
- Best Crypto Exchanges Australia 2026 - AUSTRAC-registered exchanges with Recurring Buy automation for running a real DCA strategy.
Frequently asked questions
Dollar cost averaging is the practice of buying a fixed AUD amount of an asset on a fixed schedule (e.g., $200 every fortnight), regardless of the price. The strategy averages your entry price across many purchases, reducing the impact of any single buy timing. It is the most common strategy used by retail Bitcoin investors who want exposure to the asset without trying to time the cycle. Compared to lump-sum buying, DCA reduces upside in a strong uptrend but also reduces downside if entries cluster around a cycle top.
Pick a contribution amount, a frequency (monthly, fortnightly, weekly), and a start month between January 2014 and last month. The calculator simulates buying BTC at the AUD close price for each month from the start date to the latest available month. Fortnightly and weekly frequencies are converted to an equivalent monthly contribution (e.g., $100 fortnightly equals $216.67 monthly). The simulation outputs total invested, BTC accumulated, current portfolio value, total return percentage, annualised IRR (money-weighted return), and optional CGT if sold today.
Total return is (current value minus total invested) divided by total invested, expressed as a percentage. It treats every dollar invested as equivalent, ignoring when each contribution was made. IRR (internal rate of return) is the money-weighted annualised return: the constant annual rate that would have grown each contribution to today's value. For a DCA strategy, IRR is the more honest metric because early contributions have had more time to compound. For example, $100 invested every month for 10 years totalling $12,000 finishing at $50,000 has a total return of about 316 percent but an IRR closer to 25 percent because the average dollar was only invested for about 5 years.
Yes. If you supply your marginal tax rate, the calculator estimates CGT payable as if you sold the entire DCA position today. The 50 percent CGT discount under section 115-25 of the ITAA 1997 is applied to the gross capital gain when the first BTC purchase is more than 12 months old (which is the case for any backtest with at least 13 months of contributions). Tax is then computed at your marginal rate. The estimate treats the whole position as a single disposal. In a real-world sale each BTC parcel from each DCA contribution is treated separately for CGT purposes; some parcels may not yet qualify for the discount. Use the Crypto CGT Calculator for parcel-by-parcel calculations.
Bitcoin is priced in USD on global exchanges, but Australian-resident investors measure portfolio value, contributions, and taxable gains in AUD. The AUD-USD exchange rate moves independently of Bitcoin's price, so an AUD-native DCA backtest produces different total returns and IRR than the USD equivalent (sometimes meaningfully different, especially over periods where AUD weakened or strengthened against USD). For an Australian-resident investor, AUD is the correct denomination.
A public market-data endpoint with vs_currency equals AUD, downsampled from daily to monthly closes. Data is fetched on every site build and stored as a static JSON file. The backtest runs entirely client-side using the cached static file. If the upstream source is unreachable during a build, the previous data set is preserved unchanged. Coverage starts January 2014 (the earliest reliable AUD-denominated Bitcoin price) and runs to the most recent completed month.
The earliest start month is January 2014 (the earliest available reliable AUD-denominated price). The latest start month is the most recent completed month minus one. There is no minimum holding period in the backtest, but the IRR calculation requires at least 2 months of data, and the CGT 50 percent discount only applies when the first purchase is at least 12 months old.
No. The calculator is a historical backtest tool for understanding what a specific DCA strategy would have returned in the past. It is not a prediction of future returns. Past Bitcoin performance does not guarantee future performance, and the next cycle can deviate substantially from the historical pattern. The CGT estimate is a planning tool, not tax advice. For decisions involving real money, consult a registered tax agent and a licensed financial adviser.
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