Bitcoin tools
21 BTC has 20 free Bitcoin tools. Each uses live data and shows its source and time.
Live values on this page pulled 22 Oct 2026, 21:20 London.
Calculators
Convert, estimate and test: you type the numbers, the tool uses live or historical data.
Bitcoin calculator (sats, BTC, currencies)
Converts sats, BTC and mBTC to 8 currencies at the live price.1 BTC = $81,240(Coinbase)Open →Fee calculator
Estimates the fee of a Bitcoin transaction from its size and live mempool rates.Next block: 3 sat/vB(mempool.space)Open →Mining calculator
Estimates daily BTC, profit and break-even power price for an ASIC.Open →Solo mining odds
Your chance of finding a block alone, from your hashrate and the live difficulty.Open →DCA calculator
Shows what buying the same amount every week or month would be worth, on real prices.$100 a month since 2015 → $668,235 today(blockchain.info market-price (daily USD); Coinbase spot)Open →What-if calculator
What $100 of Bitcoin bought on 1 January of a past year is worth now.Open →
Market and cycle charts
How the market is doing and where it sits in its cycles. Models are labelled as models, not forecasts.
MVRV and realized price
Market value against the average price coins last moved at.MVRV 1.54(bitcoin-data.com, 2026-10-15)Open →Rainbow chart (model)
Log-regression price bands with the formula shown. A model, not a forecast.Open →Stock-to-flow (model)
S2F ratio against the real price, and why the model diverged.Open →Volatility
Realised volatility over 7, 30, 90 and 365 days from daily closes.30-day volatility 23%(blockchain.info daily closes)Open →Fear & Greed Index
Today's index value with history and what goes into it.68/100, Greed(alternative.me)Open →Risk On/Off indicator
One 0–100 market-mood score with every formula and source shown.Score 76/100(21btc.cc, formulas on the page)Open →Cycles
Halving cycles side by side: peaks, drawdowns and days since each halving.Open →
Network
The Bitcoin network itself: difficulty, halving, hashrate and where to find a Bitcoin ATM.
Difficulty adjustment
When the next difficulty adjustment happens and by how much (estimate).Next adjustment: +3.81% (estimate)(mempool.space)Open →Halving countdown
Blocks left to the next halving and the estimated date.77,344 blocks to go, about 2028-04-11T23:00:34.088Z(mempool.space)Open →Network dashboard
Block height, hashrate, fees and mempool in one place.Hashrate 1,040 EH/s(mempool.space (3-day avg))Open →Bitcoin ATM map
Find a Bitcoin ATM near you (OpenStreetMap) with a scam warning.Open →
Checks
Check an address or transaction before you send or receive. Public data only, no sign-up.
For sites and developers
Put our data on your own site or read it from code. Free, no key.
FAQ
- Are these tools free?
- Yes. All 20 tools are free: no payment and no sign-up. The data API for AI agents is free too (read-only, no key).
- Where does the data come from?
- Every tool page names its source and the time of the data. In short: the live Bitcoin price comes from Coinbase (Kraken and Bitstamp as fallbacks), price history from blockchain.info, fees, difficulty and hashrate from mempool.space, the Fear & Greed Index from alternative.me, MVRV from bitcoin-data.com, ATMs from OpenStreetMap, currency rates from the ECB and the Bank of Russia.
- Can I embed a tool on my site?
- The live halving countdown widget embeds with an iframe: see the embeddable widget page. Other data is available through the free read-only JSON API. For the remaining tools, a plain link works.
- Do I need an account?
- No. Every tool works without signing in. A sign-in with X is only needed to post on the forum.
Embeddable widget → · Data API → · All sections →
Sources: Coinbase, blockchain.info, mempool.space, alternative.me, bitcoin-data.com · as of 22 Oct 2026, 21:20 London · each tool page shows its own sources and times