AHR999 Index

How the AHR999 Index works

Short answer: The AHR999 index is a Bitcoin accumulation indicator created by the Chinese investor ahr999. It multiplies two ratios: price ÷ 200-day DCA cost and price ÷ a power-law growth valuation based on coin age. By the author's zones, below 0.45 is a bottom-buying zone, 0.45 to 1.2 a regular DCA zone, and above 1.2 is above the DCA zone.

This page computes the AHR999 index from daily BTC/USDT closes and shows today's reading, its zone and both components. A history chart from 2018 and the share of days spent in each zone show how unusual the current reading is. It is meant for long-term Bitcoin holders who use dollar-cost averaging and want a rule-based view of relative value.

What you enter

• No user inputs; the page loads daily BTC/USDT closes from the site's BTC daily history feed (Binance public market data, with OKX as a fallback), starting 2017-08-17
• Price used: the latest daily close
• History chart from 2018, the first date with 200 days of data

What it shows

• Current AHR999 value and its zone (bottom-buying, regular DCA, or above the DCA zone)
• The two components: price ÷ 200-day DCA cost and price ÷ growth valuation
• The 200-day DCA cost and the growth valuation in USD
• History chart of AHR999 with the 0.45 and 1.2 zone lines
• Share of days in each zone over the site's data window

How to use it

1. Read the current AHR999 value and its zone label.
2. Check which component drives it: price ÷ 200-day cost shows the short-term position, price ÷ growth valuation the long-term one.
3. Compare the price with the 200-day DCA cost and the growth valuation in USD.
4. Use the history chart to see where the reading sits relative to past cycles.
5. Check the share of days in each zone to judge how rare the current zone is in the site's data.

Formula

200-day DCA cost = geometric mean of the last 200 daily closes = exp(average of ln(close)). Coin age = days since 2009-01-03 (Bitcoin genesis block). Growth valuation = 10^(5.84 × log10(coin age) − 17.01). AHR999 = (price / 200-day DCA cost) × (price / growth valuation). Zones: below 0.45 bottom-buying, 0.45 to 1.2 regular DCA, above 1.2 above the DCA zone.

Worked example

On 2026-01-01 the coin age is 6,207 days, so the growth valuation = 10^(5.84 × log10(6,207) − 17.01) = 10^(5.84 × 3.79288 − 17.01) ≈ 138,175 USD. With a hypothetical price of 90,000 USD and a hypothetical 200-day DCA cost of 100,000 USD: price / cost = 0.90, price / valuation = 90,000 / 138,175 ≈ 0.651, AHR999 = 0.90 × 0.651 ≈ 0.586, which is in the regular DCA zone (0.45 to 1.2).

How to read the result

• Below 0.45: the author's bottom-buying zone, where price is well under both its recent DCA cost and its long-term growth trend; past readings here clustered around cycle lows.
• 0.45 to 1.2: the author's regular DCA zone, where he suggested steady periodic buying.
• Above 1.2: above the DCA zone; the author called 1.2 to 5 'waiting to take off', meaning holding rather than adding, not a sell signal.
• In the author's original sample, readings sat below 0.45 about 8.5% of the time, 0.45 to 1.2 about 46.3% and 1.2 to 5 about 29.3%; the page's own zone shares cover only its data window from 2018.

Limits and cautions

• The growth valuation is a fitted power-law curve with fixed parameters (5.84 and −17.01); if Bitcoin's growth slows, it will keep rising faster than price and push AHR999 lower over time.
• The 200-day cost uses the geometric mean of closes, as most AHR999 implementations do; the true average cost of a fixed-amount DCA is the harmonic mean, which is slightly lower, so the price / cost ratio here is slightly lower than a real DCA buyer's.
• Values can differ a little from other sites because of exchange data, daily close time and whether the latest day is included.
• AHR999 is a valuation heuristic, not a timing signal; it does not predict how long Bitcoin stays in a zone.

Key terms

AHR999 index

A Bitcoin accumulation indicator created by the Chinese investor ahr999. It equals (price ÷ 200-day DCA cost) × (price ÷ growth valuation); lower values mean price is cheap relative to both its recent cost and its long-term trend.

200-day DCA cost

On this page, the geometric mean of the last 200 daily BTC/USDT closes, used as a proxy for the average cost of someone who bought a fixed amount every day for 200 days.

Growth valuation

A fitted power-law estimate of Bitcoin's value based on its age: 10^(5.84 × log10(days since 2009-01-03) − 17.01), using the author's fixed parameters.

Bottom-buying zone

An AHR999 reading below 0.45, which the author treated as a zone for adding beyond regular DCA; it covered about 8.5% of days in his original sample.

Regular DCA zone

An AHR999 reading between 0.45 and 1.2, where the author suggested steady periodic buying. Above 1.2 he stopped adding and held; he did not define a sell signal.

Common questions

What is a good AHR999 value to buy Bitcoin?

By the author's own rules, below 0.45 was the bottom-buying zone and 0.45 to 1.2 the regular DCA zone. These are historical guidelines, not guarantees of future returns.

How is the AHR999 index calculated?

AHR999 = (price / 200-day DCA cost) × (price / growth valuation), where the growth valuation is 10^(5.84 × log10(coin age in days) − 17.01) and coin age counts from 2009-01-03.

Who created the AHR999 index?

It was created by the Chinese Bitcoin investor known as ahr999 who published it with his long-term DCA strategy.

Does AHR999 above 1.2 mean sell?

No. In the author's scheme, above 1.2 means price is above the DCA zone, so he stopped regular buying and kept holding; he did not define it as a sell signal.

Sources and update cadence

• ahr999 — original article on the AHR999 accumulation index — the author's definition, the two ratios and the 0.45 / 1.2 zones with his historical zone shares
• Public Python implementation of AHR999 (CoxxA/bitcoin-ahr999-HODL) — open code using the geometric-mean cost and the growth valuation 10^(5.84 × log10(age) − 17.01)
• Binance Spot API — market data endpoints (klines) — the public daily candlestick feed this page uses for BTC/USDT closes

Further reading on this site

• DCA, Upgraded: A Zone-by-Zone Playbook Using the Cycle Thermometer
• How to Read a Bitcoin DCA Backtest Without Treating History as a Promise
• Bitcoin Power Law Fair Value Guide: Long-Term Trend, Deviation and Limits
• The 9 Indicators Behind the Cycle Thermometer: Logic, Weights & Track Record

Last reviewed: 2026-10-25