If I Bought Bitcoin Calculator

How the If I Bought Bitcoin Calculator works

Short answer: The If I Bought Bitcoin calculator shows what a past USD purchase of BTC would be worth today. It divides your amount by the BTC weekly close for the week containing your chosen date (fixed reference prices before August 2017), then multiplies the coins by the current BTC price. The result is a hindsight multiple, before fees and taxes, not a forecast.

Pick a purchase date and a USD amount to see how many bitcoins that money would have bought and what they are worth at the current price. It is meant for people who want a concrete sense of Bitcoin's long-run history, not for trading decisions.

What you enter

• Buy date: a calendar date, earliest selectable 2010-08-01, default 2017-01-01
• Amount (USD): minimum 1, default 1,000
• Data shown: BTC weekly closing prices from exchange data (Binance BTCUSDT first, with OKX, Coinbase and Bybit as fallbacks) from mid-August 2017, and a built-in list of fixed historical reference prices from August 2010 to August 2017
• Today's price: the live BTC spot price from the site ticker (Binance BTCUSDT first, other exchanges as fallback, refreshed about every 60 seconds); if the ticker is unavailable, the latest weekly close in the price history

What it shows

• The BTC price used for the purchase date
• Current value of the purchase in USD, green when above the amount invested and red when below
• Percentage gain or loss
• Number of BTC the amount would have bought

How to use it

1. Choose the buy date with the date picker.
2. Enter the amount in USD.
3. Check the BTC price shown for that date; it is the reference price the tool matched, not necessarily the price on that exact day.
4. Read the current value, percentage change and BTC amount.
5. Try several nearby dates to see how much the starting point changes the outcome.

Formula

Purchase price = the close of the latest data point whose start time is on or before the chosen date (a weekly candle from mid-August 2017; a fixed reference price before that). Coins = amount / purchase price. Value today = coins × current price. Multiple = current price / purchase price. Change % = (multiple − 1) × 100.

Worked example

Hypothetical figures: 1,000 USD on a date whose weekly close was 20,000 USD, with a current price of 50,000 USD. Coins = 1,000 / 20,000 = 0.05 BTC. Value = 0.05 × 50,000 = 2,500 USD. Multiple = 50,000 / 20,000 = 2.5×, so the change is +150%. With the default date of 2017-01-01 the tool uses its built-in December 2016 reference price of 960 USD, so 1,000 USD buys about 1.0417 BTC.

How to read the result

• The multiple depends only on the purchase price and the current price; the amount just scales the result.
• Dates a few weeks apart can give very different results, which shows how sensitive lump-sum outcomes are to timing.
• The result ignores everything in between, including drawdowns of 70% or more that a holder would have had to sit through.
• To compare with buying in instalments rather than once, use a dollar-cost-averaging backtest.

Limits and cautions

• From mid-August 2017 the tool uses the close of the weekly candle that contains your date (weeks start on Monday), so the price can be from up to six days after the date you picked rather than that day's price.
• Before mid-August 2017 it uses a sparse list of fixed reference prices, often three months apart (for example 2013-05-20 maps to the April 2013 value of 139 USD), so early results are approximate.
• Fees, spreads, taxes and inflation are not included, and USDT prices are treated as USD.
• Past returns do not predict future returns; early prices also came from thin, now-defunct markets.

Common questions

How much would 1,000 dollars in Bitcoin be worth today?

It depends on the purchase date: divide 1,000 by the BTC price on that date and multiply by today's price. Enter the date and amount in the calculator to get the current figure.

What price does the calculator use for the purchase date?

From mid-August 2017 it uses the closing price of the weekly candle that contains the date; before that it uses the nearest earlier built-in reference price, which may be several months older.

Does the result include fees and taxes?

No. It assumes the full amount bought BTC at the reference price and was held untouched, with no fees, spread, tax or inflation adjustment.

What is the earliest date I can enter?

The date picker starts at 2010-08-01, where the tool's first reference price is 0.06 USD. Prices that early are rough historical estimates from very thin markets.