Coin Age MetricsBDD
These on-chain metrics track how long coins have stayed unmoved. Dormant supply is the amount untouched for a set period; Coin Days Destroyed weights each spent coin by how long it had been held; HODL waves chart Bitcoin’s supply by age band. Old coins moving is often read as long-term holders selling.
On-chain data shows how long coins sat still before they moved. Coin age metrics turn that into signals about whether long-term holders are spending or saving.
- Category
- Cryptocurrency and Blockchain
- Reading time
- 3 min
- Also called
- Coin days destroyed, HODL waves, Dormancy metrics
- Updated
Coin age in plain words
Bitcoin Days Destroyed weights the movement of coins by age, meaning the time since each coin was previously spent.1
It is often called by its generic name, Coin Days Destroyed (CDD).1
HODL waves group supply by the time since it last moved on-chain.2
How coin age metrics are built
Track each coin's last move
Age is the time since a coin was last spent.1
Multiply amount by age
5 BTC idle 100 days = 500 coin days.
Destroy on spending
When coins move, their accumulated coin days are counted as destroyed and age resets.
Group supply by age
HODL waves show supply bands by time since last move.2
Summarise with liveliness
Liveliness ranges from 0 to 1 and rises as long-term holders sell.1
Add off-chain context
Use them with other signals to gauge long- versus short-term holders.1
Worked examples
Example 1 — Coin days destroyed
2,100 coin days destroyedHypothetically a wallet moves 5 BTC that sat for 400 days, and another moves 50 BTC held for 2 days.
| Old coins | 5 × 400 = 2,000 coin days |
| New coins | 50 × 2 = 100 coin days |
| Total CDD | 2,000 + 100 = 2,100 |
Weighting by age means the small, old transfer dominates the metric.1
Example 2 — Short-term supply growth
+30% short-term supplyHypothetically coins active in the past year rise from 5.0M to 6.5M BTC.
| Increase | 6.5M − 5.0M = 1.5M BTC |
| Percent rise | 1.5 ÷ 5.0 = 30% |
Coin Metrics saw a similar pattern as previously dormant coins re-entered circulation.3
Example 3 — A false signal
Signal may be misleadingHypothetically a CDD spike of 1,000,000 coin days comes from one 2,000 BTC wallet idle 500 days.
| Check | 2,000 × 500 = 1,000,000 |
| Share from one wallet | 100% |
Large old movements can be seizures or custody moves, such as government transfers of seized coins.1
CDD vs HODL waves
| Aspect | Coin days destroyed | HODL waves |
|---|---|---|
| Measures | Age of coins being spent | Age profile of all supply |
| Type | Flow | Stock |
| Best for | Spotting old coins moving | Long-run holder structure |
| Weakness | Spikes from single wallets | Slow to change |
Where coin age metrics are used
Cycle analysis
Gauge Bull Market tops when old coins are spent.
Sentiment
Add an on-chain view to Fear and Greed readings.
Supply pressure
Spot potential selling as dormant Liquidity wakes.
Research
Combine with Fundamental Analysis of a network.
Advantages and disadvantages
Advantages
- Built on public, verifiable data.
- Separates long-term holder behaviour from noise.
- Works across market cycles.
- Shows dormant supply.
Disadvantages
- Custody moves look like selling.
- One wallet can swamp the metric.
- Misses off-chain exchange activity.
- Providers calculate metrics differently.
Going deeper
Read as far as you need. Each level builds on the one before it.
Old coins weigh more
Beginner
CDD weights movement by how long coins were idle.1
Dormant supply
Intermediate
Some coins have stayed dormant and effectively out of circulation for years, which HODL waves make visible.2
Blind spots
Advanced
On-chain metrics do not capture activity on exchanges and other off-chain venues, so pair them with exchange data.1
Common mistakes
Reading every spike as selling
Ignoring custody or wallet reshuffles.
Mixing providers
Comparing CDD from two different sources.
Ignoring off-chain trading
Forgetting most trading happens on exchanges.
Short lookbacks
Judging a slow metric over days.
Check your understanding
Test yourself before moving on. Each answer comes with an explanation.
Key points to remember
- Coin age is time since last spent.
- CDD weights spending by age.
- HODL waves show supply by age band.
- Custody moves cause false signals.
- Use with off-chain data.
Frequently asked questions
Is high CDD bearish?
Do these work for Ethereum?
What is a HODL wave?
Further learning
- Fundamental Analysis
Where on-chain data fits.
- Leading and Lagging Indicators
Is CDD leading or lagging?
- Fear and Greed
Sentiment measures.
- Volume
Compare with trading volume.
Sources
This article is written in our own words. The sources below support the specific facts, rules and figures marked with a number in the text. Links open the original publisher’s page.
- Galaxy Digital Research. Introduction to On-Chain Analysis (opens in a new tab) Checked .
- Coin Metrics. The Coin Metrics Bitcoin On-Chain Indicators Primer (opens in a new tab) Checked .
- Coin Metrics. Making Sense of Bitcoin's Changing Supply Dynamics (opens in a new tab) Checked .
Educational content, not financial advice. Examples use hypothetical prices and simplified costs; actual fees, margin rules and regulations vary by broker, market and country. We are not affiliated with any publisher linked above. Last reviewed . Report an error or request a source credit.