Bitdeer: the company, SEAL chips and SealMiner miners

Bitdeer Technologies Group is a Singapore based company that builds miners under the SealMiner brand. It was spun off from Bitmain in January 2021 and founded by Jihan Wu, a co-founder of Bitmain, who today is also its executive chairman and chief executive officer. Since April 2023 the company has traded on Nasdaq under the ticker BTDR, having gone public through a merger with the special purpose company Blue Safari Group Acquisition Corp.

The main thing to understand about Bitdeer before you buy: selling miners is not its core business. The company is at the same time a data center operator, a cloud mining provider, a hosting provider, a miner on its own account and a cloud platform for GPU computing. In 2025 hardware brought in 108.3 million dollars out of total revenue of 620.3 million, roughly 17 percent. In the first quarter of 2026 equipment sales came to 3.7 million against revenue of 188.9 million, about 2 percent.

Technically SealMiner plays in the top league. The company designs its chips itself, has them made at TSMC, and its flagship A4 Ultra Hydro at 886 TH/s delivers 9.45 J/TH. That is the best efficiency figure in our whole catalog across every brand. SealMiner also has one of the lowest prices per terahash on the market, although prices for the A4 flagship itself have not been officially announced yet.

And here is the other side of it. Bitdeer management says it plainly: priority goes to its own mining. On the first quarter 2026 earnings call it was said that practically the entire output goes into the company's own data centers and that external sales are not being pushed at the moment. As of June 2026 its own fleet stands at 73 EH/s and about 243 thousand miners. For a buyer the main consequence is this: spare parts and service in Europe are worse for this brand than for its competitors.

The history is short, only five years, but very dense. These dates show where the promises came apart from the result.

• 2021Bitdeer is spun off from Bitmain as a separate company. At the start it is a data center operator with hosting and cloud mining. There is no hardware of its own yet.
• 2023In April it lists on Nasdaq through a merger with a special purpose company, at a valuation of about 1.18 billion dollars. Revenue for the year is 368.6 million, net loss 56.7 million.
• 2024In March the first in house chip SEAL01 is announced on a 4 nm process with a claimed 18.1 J/TH at die level, and in the third quarter it goes into production. In June a roadmap through SEAL04 is published. In September SEAL02 testing is completed. In October SealMiner A2 is announced. A hard year: revenue of 349.8 million and a net loss of 599.2 million.
• 2025In March SEAL03 is tested and external A2 shipments begin, and the A2 Pro arrives at the same time. In September the A3 series is announced. The first profitable year: revenue of 620.3 million, of which 108.3 came from hardware, and net profit of 65.6 million.
• 2025In November the company discloses that SEAL04 fell short of its stated target: instead of 5 J/TH the first design delivered between 6 and 7, and the production run slipped to 2026. The stock drops about 14 percent in a day, and a class action lawsuit from investors is filed later. There is no court ruling as of today.
• 2026In March SealMiner DL1 Air is announced, the company's first miner not on SHA-256 but on Scrypt, for Litecoin and Dogecoin. Cumulative external A2 sales reach 8.2 EH/s by this point.
• 2026In April the A4 series on the SEAL04 chip arrives. The flagship A4 Ultra Hydro delivers 886 TH/s at 9.45 J/TH. Prices have not been officially announced, and in the manufacturer's shop it is a preorder. According to the roadmap, series production of the A4 Ultra Hydro is stated for the third quarter of 2026.
• 2026In June the hydro version of the DL1 arrives at 52.5 GH/s. Own mining reaches 73 EH/s, data centers 1797 MW online. Hardware sales meanwhile fall to almost nothing: 3.7 million for the first quarter against 108.3 for the whole of 2025.

Bitdeer names its generations after the chip: A1 on SEAL01, A2 on SEAL02, A3 on SEAL03, A4 on SEAL04. Within a generation there is a Pro version with better efficiency and an Ultra version on the top miner. The Air suffix means air cooling, while Hydro or Hyd means liquid cooling. The DL1 stands apart on a different algorithm.

The asic.es catalog lists 13 SealMiner models: 11 on SHA-256 and 2 on Scrypt. On SHA-256 efficiency runs from 9.45 to 16.5 J/TH, hashrate from 226 to 886 TH/s, power from 3625 to 8372 watts. Both DL1 miners deliver 0.15 J/MH.

Seven of the thirteen models are hydro cooled: from the A2 onward a hydro version ships in every generation, and on the DL1 it came out three months after the air one.

SHA-256, models: 11

Other algorithms, models: 2

Until 2026 the brand was purely a bitcoin one. Scrypt arrived only this year with the DL1, and so far that is the only expansion.

The list is short, but since 2026 it is no longer bitcoin only.

Bitdeer is one of the few companies that designs miner chips itself. Manufacturing is outsourced to TSMC, and the official releases about the SEAL02 and SEAL03 trials say so directly. The company publishes its roadmap openly, so you can check whether the promises matched the result.

So far the roadmap and the result have not fully matched. The process node is officially named only for SEAL01, at 4 nm. For SEAL02, SEAL03 and SEAL04 the nanometers are never named, and the releases carry only general words about the process. And SEAL04 was announced with a target of 5 J/TH and a second quarter 2025 launch, while in fact the first design delivered 6 to 7 J/TH and the series began only in 2026.

Control boards

Stated chip figures by generation: SEAL01 delivered 18.1 J/TH, SEAL02 13.5 and SEAL03 9.7 J/TH, and both of the latter numbers were obtained in undervolted mode, SEAL04 from 6 to 7. Do not confuse them with the efficiency of a finished miner: an ASIC at the wall is always worse than the die. The flagship A4 Ultra Hydro shows 9.45 J/TH at the wall with a chip rated 6 to 7.

A Bitdeer hydro miner is a 2U rack unit measuring 482 by 665 by 86 millimeters and weighing about 20.5 kilograms, and those dimensions did not change from the A2 to the A4. That means racks, hoses and quick connects bought for an A2 Hyd fit an A4 Ultra mechanically. When you re-equip a site, that saves rebuilding the whole loop.

Air miners run on 220 to 277 volts single phase, hydro on 380 to 480 volts three phase. For the A4 Pro Air the manufacturer specifies a maximum input current of 20 amperes. An air ASIC weighs about 15.5 kilograms, noticeably lighter than comparable Antminer units. That shows up in installation cost too.

Hydro at Bitdeer is more than half the lineup: seven models against six air cooled ones, and in the catalog they start with the A2 generation. The brand has no immersion option.

SealMiner units run Bitdeer's own closed firmware with a web interface. It has no separate public name. The miner works over wired Ethernet only. There is no wireless network. The factory credentials are simple and must be changed right after the first login.

There are three factory modes: economy, normal and high performance. On the A2 Pro Hyd the economy mode gives 470 TH/s at 14.5 J/TH, normal 515 at 14.9, high performance 605 at 16 J/TH and 9.68 kilowatts of draw. The spec for this ASIC is a range as well, and the table above shows its lower bound of 500. In high performance mode the permitted inlet water temperature drops to 45 degrees: the manufacturer takes the thermal headroom back for the boost.

No third party firmware exists for SealMiner. The known independent builds work with Antminer and partly with Whatsminer, none of them supports SealMiner. Our AsicBoost firmware is likewise built for Antminer only. The reason is simple: few ASICs are in third party hands, because most of the output goes into the manufacturer's own fleet.

Bitdeer's terms name overclocking as grounds for warranty denial, and the same exclusion list includes unauthorized third party software. At the same time the factory firmware itself contains a high performance mode that raises consumption on hydro ASICs by a quarter. The manufacturer does not explain publicly where the line between a factory mode and overclocking runs. Clarify this with the seller before you buy.

This is the brand's weakest area. Parts are cheapest from the manufacturer itself, but it sells them only for the A2 series and only a handful of items. Some dealers resell the same units at a markup: a power supply for the A2 hydro versions, for example, turns up at almost three times the factory price. And the specialist suppliers of repair components that stock parts and chips for Antminer, Whatsminer, Avalon and a dozen other brands do not carry SealMiner in their catalogs.

There are no failure statistics for SealMiner, and we are not going to invent them. The brand is young, the first mass generation came out at the end of 2024, and most of the output went to the manufacturer's own sites. The body of independent field use that statistics normally come from simply never built up. So we go unit by unit: what you will fix yourself, and what has to go back to the factory.

There are no public failure statistics for SealMiner today: no return rate, no mean time between failures, no industry teardowns. The reason is not that the miners are perfect but that independent field use is scarce.

Independent bench tests are practically absent as well. The only review with per mode measurements known to us is a piece by an American dealer on the A2 Pro Air, and the source has an interest, because it sells that miner itself. According to its data the economy mode gave 248 TH/s at 3572 watts, normal 275 at 4112, high performance 282 at 4288. The stated 14.9 J/TH was confirmed. The measured hashrate came out above the figure in our table, but that is no surprise. The A2 Pro Air spec is given as a range of 255 to 270 TH/s at 3790 to 4050 watts. The measurement went past the upper bound of that range but stayed inside the factory tolerance of plus 10 percent, and our table shows the lower bound. Generalizing from a single sample to the whole series is still not possible.

What does exist is a documented gap between promise and result at the chip level. SEAL04 was announced with a target of 5 J/TH and a second quarter 2025 launch. In fact the first design delivered 6 to 7 J/TH, the series slipped to 2026, and the company switched to developing two independent designs in parallel. After this information was disclosed in November 2025 the stock fell roughly 14 percent in a day and investors filed a class action. These are the plaintiff's claims, and there is no court ruling.

General industry benchmarks, true for any ASIC: a service life of four to seven years with proper maintenance, a fan resource of 40 to 70 thousand hours, and capacitors in power supplies aging noticeably after two or three years. Every extra 10 degrees on the die roughly doubles the rate of degradation.

Efficiency went from 16.5 J/TH at the end of 2024 down to 9.45 by spring 2026. Three chip generations in eighteen months.

Within a single generation of this brand, air and hydro deliver identical efficiency: on the A3 Pro both versions are 12.5 J/TH, on the A4 Pro both are 10.9. Hydro gives you power density and quiet, and it saves nothing on consumption per terahash.

On consumption per terahash SealMiner is today on a par with the best on the market, and on price per terahash it undercuts the competition. If the question came down to hardware alone, the choice would be obvious.

But it does not come down to hardware. Along with profitability, count what you will do when a miner fails. There are no hash boards either from the manufacturer or on the secondary market, independent workshops will not touch the brand, and you only find out where the service center is when you file a claim.

Calculate the return of a specific model →

A comparison across ten criteria as of August 2026. Specifications come from the manufacturers, and the ratings for availability and service are our own.

On hardware SealMiner wins on the two criteria that matter most: efficiency level with the leader and one of the lowest prices per terahash. It loses on availability, spare parts, repair, firmware and service in Europe.

If you run a large site, have your own maintenance staff and are ready to keep spare miners for swaps, SealMiner gives you the best economics on the market. If you will own one ASIC or a handful and expect to take repairs to a local technician, buy a brand with a developed service network.

Hash board repair. The main risk of the brand. SEAL chips are not available on the open market, neither are test fixtures or schematics, and independent workshops will not take on SealMiner. Any serious board failure means a return to the manufacturer with unknown turnaround. Plan spare miners for swaps in advance.

Unknown service center. The list of sites has never been published, and the specific address is named only when a claim is opened. You pay for shipping there. For a buyer in Spain that means logistics and timelines stay unknown until the day something breaks.

Sockets and breakers. Rated draw for the air miners is 3625 to 3790 watts, but on the top bins of the A2 Pro Air consumption approaches 4 kilowatts, and a dealer measurement gave 4112 watts. For the outdated C19 and C20 connectors that is already past the limit. When retrofitting an older site this is the most common hidden cost. The manufacturer's own materials disagree on whether hydro ASICs ship with power cables, so confirm this with the seller before paying.

Breaching the hydro loop rules. Bitdeer is stricter here than its competitors. The list of warranty exclusions names only one thing outright, operating the miner without a connection to the prescribed heat rejection system, but breaking the other requirements of the manual is easily treated as improper operation. Copper pipes are prohibited, the coolant must be distilled water with an inhibitor and antifreeze, and an expansion tank plus a 3.5 bar valve are mandatory.

Starting a hydro miner with air in the loop. The manufacturer explicitly forbids applying power before the air has been fully purged. The order is strict: purge the air, start the pumps and cooling, and only then switch the miners on.

Water that is too cold. The lower inlet limit is 20 degrees Celsius. Coolant that is too cold produces condensation inside the ASIC.

A blurred line between mode and overclocking. The factory high performance mode raises consumption on hydro miners by a quarter, while overclocking is named in the warranty terms as grounds for refusal. The manufacturer does not explain where that line falls. Get it in writing from the seller.

Prepayment with no right of return. In the official store, cancellation, exchange and return are not supported once an order is placed. The contract leaves the shipping queue to the seller's discretion: usually in order of confirmed full payment, but with no guarantee. On a large order that is a risk in its own right.

Ten points specific to this brand. The general rules on ventilation and dust apply here just as they do everywhere else.

1. Check your connectors before buyingAn air miner draws 3625 to 3790 watts on paper, and on the top bins of the A2 Pro Air, once you count the tolerance and the dealer measurement, the draw is already around 4 kilowatts. The outdated C19 and C20 connectors are not rated for such a load. You need a connector rated for the actual current, not a C19. For hydro ASICs, ask the seller whether power cables are included: the manufacturer's materials contradict each other on this.
2. A dedicated line for every minerFor air cooled units at 230 volts that is 16 to 18 amps. With the eighty percent rule for continuous load you need a 25 amp breaker, 4 mm² cable and a residual current device to local code. The manufacturer explicitly prohibits extension leads and power strips.
3. Keep the air inlet between 20 and 35 degrees CelsiusThe spec allows more, but the manufacturer does not publish a specific ceiling for air. There is no independent data at all on how the ASIC behaves at the edge of the range. Without per chip telemetry, do not go near the maximum.
4. Follow the hydro loop rules to the letterStainless steel only, copper is prohibited. Distilled water with a corrosion inhibitor and antifreeze. Flow no lower than 10.2 liters per minute per miner, inlet pressure no higher than 350 kPa. Filter no coarser than 100 mesh, plus a 10 micron side stream filter.
5. Respect the hydro startup orderFirst purge the air completely, then the pumps and cooling, and only then power to the miners. When a miner is disconnected from the loop it must be drained within two hours.
6. Pick the mode that suits your tariffEconomy mode gives better efficiency. High performance mode gives more hashrate at worse consumption, and it narrows the permitted water temperature to 45 degrees Celsius. At Spanish electricity prices, economy mode is almost always the better deal.
7. Change the factory credentials immediatelyThey are identical on every miner and widely known. Only wired Ethernet works, and there is no wireless. On a farm, assign static addresses.
8. Configure backup poolsA primary and two backups. Then a pool going down does not cost you a minute of downtime: the miner simply moves to the next address.
9. Budget for spare ASICs to swap inWith this brand that is not being overcautious: repairing a hash board means shipping to the manufacturer, and the terms give no turnaround times.
10. Buy from a seller with an EU legal entityThen the local rules on seller liability apply, and it is the seller, not you, who deals with service and logistics. Buying direct from the manufacturer puts all of that on the buyer, customs clearance included.

Figures from our catalog and from the company's public reporting.

• 2021The spin off from Bitmain. A player arrived on the market with the experience of the largest manufacturer. Its own hardware came out only three years later.
• 2023Listing on Nasdaq. The company's finances, shipment volumes and risks became visible from outside. A seller can now be checked against quarterly filings.
• 2024The first in house chip, SEAL01 on a 4 nm process. The company stopped being purely a data center operator and became a manufacturer.
• 2024A public chip roadmap through SEAL04 with concrete figures and dates. Competitors usually show their specifications together with the product.
• 2025The first profitable year: revenue of 620.3 million dollars and net profit of 65.6 million. Equipment sales brought in 108.3 million.
• 2026The A4 Ultra Hydro at 886 TH/s and 9.45 J/TH. That is the best efficiency in our whole catalog across all brands.
• 2026Moving beyond bitcoin: the SealMiner DL1 on Scrypt for Litecoin and Dogecoin, in air and hydro versions.
• 2026Self mining of 73 EH/s and 1797 MW of data center capacity online. The manufacturer runs the hardware in house first, and that is where almost all the output ends up too.