Background: browser flasher, the new 2.0 and open source
What technically happens when you click "Connect & Flash", what BitMiner24 Firmware 2.0 and its 285 % gain can do, and which route to use when.
memory How does the browser flasher work technically?
The bitminer24 browser flasher is built on ESP Web Tools, an official open source library from Espressif, the maker of the ESP32-S3 chip inside the Nerdminer V2. As soon as you click the flash button, your browser requests access to the USB port through the Web Serial API. The ESP32-S3 is put into boot mode automatically, the firmware file is streamed into your RAM, verified and then written to the chip's flash memory. That is exactly the procedure esptool.py uses on the command line. No communication with our servers takes place during flashing: your computer talks directly to the miner.
lock What is the Web Serial API, and is it safe?
The Web Serial API is a W3C specification that lets a web page talk to serial devices on the USB port, after explicit user confirmation. Every connection requires a click in a browser dialog where you pick the specific port. The page only gets access to the one port you grant. All of it runs 100% client side in the browser: no data upload, no cloud server, no telemetry. Chrome, Edge, Brave and Opera currently support the Web Serial API on desktop operating systems. As of 2026, Safari, Firefox and mobile browsers do not.
history Firmware versions at a glance: what does 2.0 bring?
We develop our BitMiner24 Firmware 2.0 in the open on GitHub, including every measurement and the approaches that provably gained nothing. The original project NerdMiner_v2 by BitMaker remains the foundation and stays selectable as version 1.8.3.
- 1.6.x (legacy): typically ~150–180 kH/s, more frequent Wi-Fi drops.
- 1.7.x (transition): typically ~190–210 kH/s, more stable connections.
- 1.8.0 – 1.8.3 (original): typically ~220–250 kH/s, reworked hashing routine, final bug fixes. Still selectable.
- BitMiner24 2.0 (default, recommended): around 300 kH/s at about 52 °C, roughly +285 % over the stock firmware and about +20 % over the best original release. A complete rebuild on ESP-IDF 5.5, open source under MIT. Exclusive to it: the solo block find tracker, which no other NerdMiner firmware has.
Around 300 kH/s instead of roughly 78 kH/s on the same device, because the ESP32-S3 SHA engine does the work.
Roughly 52 °C instead of over 60 °C, about 345 % more hashing per degree of waste heat.
Hashrate, temperature, shares and uptime in the browser, no cable.
Two app slots with automatic rollback if an update fails to start.
Uptime, shares, best difficulty and block finds are kept.
64 vectors at boot, spot checks while running, every hit recomputed.
Only the inefficient software share is throttled, never the frugal engine.
A screen no other NerdMiner firmware has: it shows when someone last found a Bitcoin block solo anywhere in the world, the current jackpot and how often that happens. Built by us.
Mining, clock, network, price and solo tracker. Setup via QR code.
What it looks like on the device:
Before and after: the new design
On the left the original 1.8.3 interface, on the right the redesigned 2.0. Less clutter, larger values, easier to read from a distance.
Mining screen
Bitcoin network
Bitcoin price
Clock and block
compare_arrows Browser flasher vs esptool: which one when?
Both methods install the same firmware. Only the workflow differs:
| Criterion | Browser flasher (this page) | esptool / klassisch |
|---|---|---|
| Time needed | ~3 minutes, no setup | ~15 minutes including Python & drivers |
| Software required | Just a Chromium browser | Python 3, esptool.py, USB-Treiber |
| Operating system | Windows, macOS, Linux (Desktop) | Windows, macOS, Linux |
| Browser requirement | Chrome, Edge, Brave, Opera | None, it runs in a terminal |
| Eigene Custom-Firmware | No, only our verified builds | Yes, any .bin file |
| Recommended for | 99% of users, the standard update | Entwickler & Custom-Builds |
We only recommend the classic esptool method if you want to build your own custom firmware, are using a browser without the Web Serial API, or simply prefer the command line for another reason. There is a separate step-by-step esptool guide for the Nerdminer V2 in the knowledge section.
code About the open source firmware (MIT)
By default we ship our own BitMiner24 Firmware 2.0. It is a complete rebuild on ESP-IDF 5.5 and reaches around 300 kH/s instead of roughly 78 kH/s on the same device, about 285 % more hashing power, while running cooler (around 52 °C instead of over 60 °C). The full source is open under the MIT licence: Bitminer24/bitminer24-firmware, including every measurement and the approaches that provably gained nothing. We built on the original project NerdMiner_v2 by BitMaker and the NerdMiner community, which is also MIT licensed. If you prefer the unmodified original, pick version 1.8.3; you can switch back at any time.
shopping_bag Still need hardware?
We sell both devices with a printed guide, preconfigured firmware and 2 to 3 business days delivery from Stuttgart: the Nerdminer V2 from 48.99 € as the entry-level device and the NerdNOS for considerably more hash rate. Both with the full 2-year statutory warranty and support from Germany.
Ships from Stuttgart in 2–3 working days. German-language support.
