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Lifespan report · Oct 11, 2026 · 3 min read
Antminer S15 lifespan report: it paid for itself in a year and still lost to buying bitcoin
Bought at launch at the bottom of the 2018 bear market and run on 3.9¢ power for six and a half years. It mined 0.55 BTC, made 3.6 times its price after power, and was worth more in 2021 than it cost. The same dollars in bitcoin did 8% better.
Bitmain Antminer S15 (28 TH/s)
TL;DR
- It made money. $1,475 at launch in December 2018; $3,864 of profit after power, the price and depreciation, every bitcoin sold as mined.
- It paid for itself in exactly a year, on 21 December 2019.
- It still lost to buying. The same dollars put into bitcoin on the same days would have bought 0.600 BTC; the S15 mined 0.555 BTC, 8% less.
- Why: it was bought when bitcoin itself was cheapest. At $3,700 a bitcoin, dollars bought a lot of it. A machine has to beat that.
- It was overtaken within four months by the S17, which did the same work on a fifth less power per terahash.
Launched at the bottom of the market
Bitmain priced the Antminer S15 at $1,475 in November 2018, its first machine on 7-nanometre chips: 28 TH/s at 57 joules per terahash. The first units shipped in the last days of December, with bitcoin at $3,728, close to the lowest it would trade in that whole cycle.
This report follows one S15 bought at that price, from its first day to its last, on 3.9¢ power (our cheapest site's rate today), 95% uptime and a 2% pool fee, switched off on any day it would lose money. Its life ends on the last day its trailing month still paid for its power. It is the method behind our study of mining against buying, and the charts compute it live.
Three-quarters of its bitcoin in two years
In 2019, its first full year, the S15 mined 0.30 BTC: more than half of everything it would ever mine. By the end of 2020 it had 74% of its lifetime output. After the May 2020 halving each year brought less: 0.11 BTC in 2020, 0.06 in 2021, 0.04 in 2022.
The bitcoin it mined later was worth far more per unit, which is why the dollars kept coming even as the bitcoin slowed. Its most profitable year was 2021, with $2,409 after power from just 0.064 BTC.
A year to pay for itself
Sold as mined, its bitcoin covered the $1,475 price on 21 December 2019, a year after it shipped. Power at 3.9¢ cost $1.49 a day, against about $5.50 a day of bitcoin through 2019.
From there it was profit, in the 2021 bull market especially: its best month, August 2021, made $255 after power.
It paid for itself one year to the day after it shipped.
Worth more in 2021 than it cost
In March 2021, machines of its class were selling for about $95 per terahash, and a used S15 for about $2,650: 80% more than it cost new two years earlier. Anyone who sold then got the machine back for free.
Then the value collapsed. By December 2023 its class sold for about $3 per terahash, under $100 a machine, and soon after there was no market for it. Kept to the end, it lost its whole price, about $220 a year of its life.
Two halvings, and the last good month
The May 2020 halving cut what it earned in half, but at 3.9¢ it kept running every day of 2020 through 2023. The April 2024 halving was the one it could not absorb: it ran 162 days that year and 69 in 2025, only when fees or price made it worthwhile. It stopped for good on 25 August 2025. At 57 J/TH and 3.9¢ it needed hashprice around $57 per petahash a day; by then a petahash earned about $54.
The full accounts
Over 6.7 years of life the S15 ran on 2,066 days and mined 0.555 BTC. Sold as mined, that brought in $8,425. Power took $3,086, 37% of it. Take away the $1,475 price, with nothing back at the end, and it left $3,864 in profit: 3.6 times its price in cash from mining. Each bitcoin cost $8,222.
Kept instead, its 0.555 BTC were worth $45,999 at bitcoin's price on 11 October 2026.
Was it worth buying?
It made money, and plenty of it. But the fair test is against buying bitcoin with the same dollars on the same days: $1,475 in December 2018 and every power bill after. That would have bought 0.600 BTC. The S15 mined 0.555 BTC, 8% less.
Two things worked against it. It was bought at the very bottom of the 2018 bear market, when every dollar bought the most bitcoin it would for years. And it was overtaken almost at once: four months later Bitmain launched the S17, at 45 J/TH against the S15's 57, which mined 29% more than buying over its own life. Machines bought around a market bottom only win when they are the efficient ones.
Mining output depends on bitcoin's price, difficulty and uptime, and isn't guaranteed. These are past results, not a forecast.
Mining beats buying when the machine is cheap relative to what it earns. In December 2018, bitcoin itself was cheaper still.
Which machines this covers
Disclosure
Firsthand Bitcoin sells and hosts mining hardware, including this machine. No manufacturer, distributor or affiliate programme paid for or reviewed this page and we take no commission on the links above. Historical figures are computed from daily bitcoin price and network hashprice, each day valued at its own prices. Nothing here is investment advice.