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YOU CAN BUILD THE DESK CLOCK THAT FLASHES FROM YOUR BROWSER IN A MINUTE

Flash an ESP-powered desk clock from a browser tab in under a minute — no IDE, no drivers, no serial cable troubleshooting.

by M-Factory

FULL CAD BOM FIRMWARE DOCS

DisplaysHome

Built withESP32ESP8266

difficulty
●●○○○
time
an evening
license
Custom source-available (non-commercial, no redistribution)
repo
repo ACTIVE1,548 stars

WHAT YOU’LL NEED

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COMPAREE VERDICT

ESPTimeCast solves the single most frustrating part of ESP microcontroller projects: getting the firmware onto the board. The web installer at esptimecast.com flashes the firmware directly from a browser tab with no toolchain, no drivers and no guessing which USB port is which. After flashing you connect to the board's own WiFi access point and finish setup there. The hardware itself is straightforward — an ESP8266 or ESP32 wired to MAX7219 LED matrix modules — and the result is a clean, readable desk clock that pulls time over NTP and weather from OpenWeatherMap. The part that will take longest is not the wiring or the flashing, it is the enclosure: the official case is a paid STL, so builders either buy it, print a free community MAX7219 case, cut a wood box or mount the bare modules on standoffs. The license is the catch: this is source-available, not open source. You can use it, modify it and share photos of it, but you cannot redistribute the code or sell derivatives. If you want to understand how the web installer works or adapt it for another project, the source is there to read, but you cannot fork it into a new product. For a desk clock you build once and leave running, that restriction will not matter. For someone building a commercial product or contributing to the ecosystem, it will.

GOOD TO KNOW

  • —Firmware, web installer, configuration portal and a recommended parts list are all present and maintained.
  • —The official case is a paid STL download (Printables, Cults3D); free MAX7219 enclosures from the community also fit.
  • —Licence is source-available, not open source: private non-commercial use and modification are permitted, redistribution is prohibited.
  • —The licence explicitly allows sharing photos and videos of builds with credit.
  • —Officially tested on Wemos D1 Mini, ESP32 Dev Module, ESP32-C3 SuperMini, and multiple ESP32-S2 and ESP32-S3 boards.
  • —Requires an OpenWeatherMap API key (free tier exists, requires account creation).

Parts to buy

4 items

From our check of the build. Exact quantities and part numbers are in the creator’s BOM.

  • ESP8266 or ESP32 dev board from the tested listFind
  • 4-in-1 MAX7219 8x32 dot matrix moduleFind
  • Dupont jumpersFind
  • 5V USB power supplyFind

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Can I build this?

Printnothing required (case is builder's choice — print, wood, bare mount)
BuyESP8266 or ESP32 dev board from the tested list, a 4-in-1 MAX7219 8x32 dot matrix module, dupont jumpers, 5V USB power supply
Toolsweb browser with Web Serial support (Chrome, Edge, Firefox or Brave), soldering iron for header pins if modules arrive without them, WiFi network, OpenWeatherMap account (free tier)
Skillsbasic jumper wiring, can follow a pinout diagram, comfort opening a web page and pasting an API key — no programming required
Timeflashing and setup take under ten minutes, wiring takes thirty minutes to an hour depending on solder experience, enclosure is unbounded
CostLow — an ESP8266 or ESP32 board, a 4-in-1 MAX7219 8x32 matrix and a 5 V USB supply; the creator gives no prices, but these are common, inexpensive parts.
SafetyNone beyond ordinary electronics care. Powered by 5V USB or barrel jack, no mains voltage, no lithium cells to manage.

Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.

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Gallery

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Start here

Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.

  1. 1.Read the supported boards list in the README and confirm you have one (or order a Wemos D1 Mini or ESP32-C3 SuperMini if starting from scratch) (Board compatibility matters — not every ESP variant is tested)
  2. 2.Order MAX7219 dot matrix modules (four-module chain is the standard width) and dupont jumpers(Modules with headers pre-soldered save time; without them you will need to solder pin headers on)
  3. 3.Create a free OpenWeatherMap account and generate an API key (The free tier is sufficient; key activation can take a few minutes)
  4. 4.Go to esptimecast.com and flash the firmware from the browser(Requires a Web Serial browser — the README lists Chrome, Edge, Firefox or Brave; Safari does not work)
  5. 5.Wire the MAX7219 modules to the ESP following the pinout in the README, connect to the board's WiFi AP, and complete setup in the configuration portal (The board creates its own access point on first boot — connect to it and navigate to the IP shown on the matrix)

Resources

Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.

KNOWN ISSUES

  • The licence prohibits redistribution and commercial use — if you are building this to understand web-based ESP flashing for another project, you can read the source and keep a private, non-public fork for personal changes, but you cannot publish, redistribute or sell any version of it.
  • Not every ESP board is tested — stick to the supported list (Wemos D1 Mini, ESP32 Dev, ESP32-C3 SuperMini, ESP32-S2/S3 variants) or expect to troubleshoot pinouts yourself.
  • The installer needs a Web Serial browser — the README lists Chrome, Edge, Firefox or Brave; Safari will not work, and an outdated browser may report the feature as unsupported.
  • A new OpenWeatherMap API key is not always active immediately — if the weather does not appear after setup, give the key some time to activate and reboot the board.
  • The official case is a paid STL — if you want a free one, pick a community MAX7219 enclosure and check it matches your module count before printing.
  • Some MAX7219 modules ship without headers soldered — if you are not comfortable soldering pin headers, order modules that arrive pre-assembled.

Can I use this commercially or redistribute the code?

No. The licence permits private non-commercial use and modification only. You can share photos and videos of your build with credit, but you cannot redistribute the firmware or sell derivatives.

What if my ESP board is not on the supported list?

It may still work, but you will be troubleshooting pinouts and WebSerial compatibility yourself. The supported boards (Wemos D1 Mini, ESP32 Dev Module, ESP32-C3 SuperMini, ESP32-S2/S3 variants) are tested and documented.

Do I need the Arduino IDE?

No. The entire point of this project is that you do not — the firmware is flashed from a browser tab at esptimecast.com using WebSerial.

How many MAX7219 modules do I need?

Four. The firmware is written for an 8x32 matrix, which is four 8x8 MAX7219 modules in a chain — buy a ready-made 4-in-1 module to save wiring.

Does the free OpenWeatherMap tier work?

Yes. The free tier provides sufficient API calls for a desk clock that updates every few minutes.

Community builds

No community builds yet — be the first, we feature the best ones.

Discussion1

FROM THE COMPAREE TEAM

More than 1,500 people have starred this project, largely because it flashes from a browser tab with no IDE or drivers. What would finally get you to try an ESP project if the toolchain was this frictionless?

CompareeTEAM1mo agoedited

Practical notes from our verification: the web installer lives at esptimecast.com and flashes the firmware straight from a browser that supports Web Serial (the README lists Chrome, Edge, Firefox and Brave). The repository is actively maintained, with more than 1,500 stars and commits in October 2026, and the README opens with a demo video from the creator. For an enclosure, the official ESPTimeCast case is a paid STL download, and plenty of free community MAX7219 cases work too. The single biggest decision before ordering parts is the licence: it is source-available for personal, non-commercial use only and forbids redistribution and selling devices preloaded with the software. Building one for your desk is fine; selling clocks or republishing the firmware is not. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.

M-Factory

M-Factory is an Osaka-based creative studio working across web design, laser cutting and 3D printing. Its ESPTimeCast clock installs from a browser-based web installer with no Arduino IDE or driver setup, has been featured by Hackaday, XDA Developers and Hackster, and has passed 1,400 stars on GitHub.

GitHub

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DISCLAIMER

  • Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
  • Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
  • Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
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