How do you measure a price in Bitcoin?

For each month, take the item's dollar price and divide by Bitcoin's four year simple moving average at that month's end. The result is how many Bitcoin the item cost that month. Charts also keep a spot series that uses the last daily close of the month instead of the average.

Why use a four year average instead of the daily Bitcoin price?

Bitcoin's dollar price swings hard over months and years. Dividing by the spot price makes short boom and bust cycles dominate the chart. A four year simple moving average of daily closes smooths that noise so the long term direction of each item's Bitcoin price is readable. The honest chapter on the homepage shows every completed four year period so you can judge the volatility yourself.

Where does the data come from?

Bitcoin closes come from public exchange APIs (Kraken primary, Coinbase fallback). US consumer and housing series come from the Bureau of Labor Statistics, the Census Bureau, HUD, and the Federal Reserve via FRED. Big Mac prices come from The Economist's Big Mac index. Ford F-150 base MSRP and Apple iPhone base launch prices are collected by hand from official pricing guides and press releases.

How often are the numbers updated?

Numbers are refreshed nightly from the same public sources. Monthly and yearly series usually sit still between official releases; Bitcoin usually moves every night.

Is this financial advice?

No. The site is a record of public prices measured with two rulers. It does not predict the future, recommend buying or selling anything, or include fees, taxes, or exchange spreads.

How it works

Every chart on this site is the same idea twice: the price of an everyday thing in dollars, and that same price divided by Bitcoin. The numbers come from public sources and are refreshed nightly. Nothing here is a prediction or a recommendation. It is a record of what has happened so far, measured with two rulers.

Data as of September 23, 2026.

The two rulers

For each item we keep a monthly dollar series and two Bitcoin series:

Four year average (what the charts show). Each month's dollar price is divided by Bitcoin's four year simple moving average of daily closes, ending on the last calendar day of that month. The window is 1,461 days (four years including one leap day). When fewer than 1,461 days of history exist, the average uses whatever daily closes are available up to that date.
Spot (kept in the data, not the default chart). The same dollar price divided by the last daily Bitcoin close of that month. Useful for checking the average against the raw market, but noisier to read.

Takeaway percentages on item pages compare the first month of the series with the latest month, using the four year average series for Bitcoin and the dollar series for USD.

Why a four year average

Bitcoin's dollar price does not move in a straight line. It has fallen more than 70% four separate times. If you divide grocery prices by the daily spot, short boom and bust cycles swamp the chart. A four year average is long enough to span a full market cycle and short enough to still move when the long term trend changes.

That choice is also why the homepage has an honest chapter: every completed four year holding period in the daily Bitcoin history, one tile per start month. A period counts as "ahead" when Bitcoin's dollar price finished higher than it started, which means the dollar bought less Bitcoin at the end. Green and red are that outcome, not a grade.

How a monthly series is built

Item charts start in July 2015, the first month with continuous daily Bitcoin closes in our history, and run through the latest month that has a close. Sources arrive at different cadences (monthly, quarterly, twice a year, or yearly). Before dividing by Bitcoin we forward fill each source to monthly frequency: every month carries the most recent published price at or before that month. Months before the first observation are skipped.

That means a yearly sticker price holds flat across the twelve months of its model year, a quarterly home price holds until the next release, and a twice yearly Big Mac price holds until The Economist publishes again. Forward filling does not invent new observations; it only repeats the last known one so the Bitcoin denominator can be applied month by month.

Bitcoin price

Bitcoin is one USD close per UTC day, taken from public exchange market data. The primary source is Kraken's daily XBTUSD candle; if that is unavailable, the same close comes from Coinbase's public BTC-USD market. Earlier history was assembled the same way from public exchange data.

Item and macro sources

Unless noted, series are pulled through FRED (St. Louis Fed) from the underlying US statistical agencies.

Big Mac: US dollar price from The Economist big-mac-data CSV (dollar_price where iso_a3 is USA). Published roughly twice a year; forward filled to monthly.
Gasoline: US city average retail price for all types, dollars per gallon. BLS via FRED APU000074714. Monthly.
Eggs: US city average price of grade A large eggs, dollars per dozen. BLS via FRED APU0000708111. Monthly.
Rent: CPI rent of primary residence index (not a dollar rent check). BLS via FRED CUUR0000SEHA. Monthly. The chart plots the index itself, then the same index divided by the four year Bitcoin average.
Median home: Median sales price of houses sold in the United States. Census Bureau and HUD via FRED MSPUS. Quarterly; forward filled to monthly.
Ford F-150: Base MSRP of the XL regular cab by model year, destination charge excluded, collected by hand from Ford pricing guides. One row per year; forward filled across that model year.
iPhone: Apple US launch price of the base iPhone by release year (6s through current), before tax, collected by hand from Apple's press releases. 2020 uses the unlocked iPhone 12 price; the widely quoted lower figure required carrier activation. One row per year; forward filled across that year.
Consumer prices (CPI): All-items CPI, FRED CPIAUCSL. On the homepage story the series is rebased so 1970 equals 100, alongside M2. The opening cart figure uses the ratio of the latest CPI to July 2015.
M2 money supply: FRED M2SL, monthly, rebased to 1970 equals 100 on the homepage chart so it can be read next to CPI.

The calculator

The calculator answers a different question: if you had spent dollars on Bitcoin in a past year, what would that Bitcoin be worth at the latest daily close?

One purchase divides the amount by that year's average daily close.
Yearly pay splits the amount across twelve months and converts each twelfth at that month's average daily close, then sums the Bitcoin.

Entry prices are averages of every daily close in the window. Nothing is anchored to a low. The "same dollars today" comparison uses that year's average CPI over the latest CPI. Years run from 2013 through the last completed calendar year. No fees, taxes, or exchange spreads are included.

How often this updates

Numbers are refreshed nightly. Bitcoin usually gains a new daily close. FRED series and The Economist Big Mac index are checked each night too, but monthly, quarterly, and twice yearly sources often return the same values between official releases. The F-150 and iPhone series are updated by hand when a new model year or launch price is published. If a source is briefly unavailable, the site keeps the last good numbers until the next successful refresh.

What this is not

Not financial advice, and not a forecast.
Not an argument that any particular purchase should have been made in Bitcoin.
Not adjusted for quality changes, taxes, fees, regional price differences, or the full options list on a truck or phone. Each series is one published yardstick, applied consistently.
Not a live ticker. You are reading the latest nightly refresh.

Questions

Why July 2015 for the item charts?

That is the first month with continuous daily Bitcoin closes in the history we carry forward. The calculator can go back to 2013 because it only needs Bitcoin and CPI averages, not the item series.

Why show rent as an index?

The official CPI rent series is an index of how rents change, not a national average rent check. Plotting the index keeps faith with the source; dividing that same index by Bitcoin still shows whether rent rose or fell relative to Bitcoin.

Do you cherry pick start dates?

Item pages all start at the same month. The honest chapter shows every completed four year window, not a single flattering interval. The calculator uses yearly and monthly averages rather than the cheapest day of the year.

Can I reproduce the charts?

Yes. The dollar sources above are public. Divide each month's dollar value by the average of daily Bitcoin closes over the prior 1,461 days ending on that month's last calendar day. Sparse sources should be forward filled to monthly first.

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