A curated list of Advent calendars to help you become a better developer.
- Some calendars feature classic coding challenges.
- Others provide articles on web technologies, programming languages, UI/UX, Agile, and more.
I wasn't sure how to categorize them, so I grouped them into two broad sections that seemed most logical. Suggestions are welcome!
Feel free to submit a pull request to add additional Advent calendars that would benefit developers.
| Name | Description | Start Date | End Date | Archives |
|---|---|---|---|---|
| Advent of Code | Programming Puzzles for variety skill sets and skill levels that can be solved in any programming language you like. | 1st Dec | 12th Dec | |
| 2025 Advent Programming Challenges Calendar | Solve a new programming challenge every day until Christmas. | 1st Dec | 25th Dec |
Previous years2024 |
| Advent of Code 2025 with Kotlin | Solve Advent of Code challenges using Kotlin and win prizes. | 1st Dec | 25th Dec |
Previous years2020-2024 |
| Advent of SysAdmin 2025 | The Advent of Sysadmin is a 12-day Advent calendar of Linux and DevOps challenges of different difficulties | 1st Dec | 12th Dec | - |
| Advent of Puzzles | Solve puzzles to reach the next puzzle | 1st Dec | 25th Dec |
Previous years2024 |
| Advent of Code with NoCode | Solve Advent of Code challenges using NoCode - visual scripting on this playground. | 1st Dec | 25th Dec | - |
| Advent of Ada/SPARK 2025 | Solve Advent of Code using the Ada programming language, AdaCore will donate $10 to the Ada Developers Academy, AdaCore will donate $20 if the solution is implemented in SPARK with at least proof of absence of run-time errors up to a total of $5,000 | 1st Dec | 12th Dec |
Previous years2024 |
| AdventJS | 24 JavaScript challenges. Every day, a new programming challenge and a giveaway! | 1st Dec | 24th Dec | |
| SQL Advent Calendar 2025 | 24 days of SQL challenges to level up your skills this holiday season. | 1st Dec | 24th Dec | - |
| Advent of Craft | This edition reuses the 2023/2024 challenges as memories, adds new Key Activations, and focuses on reflection, experimentatin and community discussions. | 1st Dec | 24th Dec | |
| Math+ | MATH+ Advent Calendar invites you to discover the beauty and power of Math beyond the subjects covered in school. | 1st Dec | 24th Dec |
Previous years2004-2023 |
| Advent of Cyber 2025 | Tackle interactive tasks across various areas of cyber – from hacking actual machines to defending digital realms. Prizes and certificates on completion. | 1st Dec | 24th Dec | |
| SANS Holiday Hack Challenge 2025 | High‑quality, hands‑on cybersecurity challenges for all skill levels. Play to learn, practice, and compete for exciting prizes. | 1st Dec | 24th Dec |
Previous years2024 |
| Debug December | A series of 24 coding challenges where you solve bugs! One challenge unlocks each day. 5 raffles to win swag and a chance to win a PlayStation 5. | 1st Dec | 24th Dec |
Previous years2011-2024 |
| Weekly Challenge Advent Calendar 2025 | Daily coding challenges from the archive of weeklychallenges. | 1st Dec | 24th Dec | |
| Fermyon Advent of Spin | Write and deploy Spin applications every week. Spin is an open-source framework for building and running serverless applications powered by WebAssembly | 1st Dec | 24th Dec | |
| Kodekalender | 24 Programming tasks, enter the correct answer to participate in a draw to win. | 1st Dec | 24th Dec | - |
| 24 Pull Requests | Make 1 contribution to an open source project everyday. Login to track your contributions. | 1st Dec | 24th Dec | - |
| Maker Advent Calendar - The 12 Projects of Codemas | 12 exciting days of fun projects including new components to play with every day. The first day of the calendar includes a Raspberry Pi Pico H, Micro-USB cable and breadboard to get you set up | 1st Dec | 24th Dec | -- |
| Name | Description | Start Date | End Date | Archives |
|---|---|---|---|---|
| HTMLHell | 24 authors from all around the world share their knowledege about accessbility, performance, usability and security. | 1st Dec | 24th Dec | |
| Festive Tech Calendar 2025 | Learn various new technologies everyday with videos from the community. | 1st Dec | 31st Dec | - |
| BekkChristmas | Learn from the over 100 articles from Bekk engineers, designers, strategists, product owners and team leads. | 1st Dec | 24th Dec | |
| 24 Jours De Web | 24 authors publish articles covering topics related to web. | 1st Dec | 24th Dec | |
| PerfPlanet | Articles related to web performance and speed. | 1st Dec | 31st Dec | |
| Perl Advent Calendar | Explore a new Perl module each day for the twenty-four days of advent, and an extra module on Christmas day | 1st Dec | 25th Dec | |
| C# Advent Calendar 2025 | Two new C# blog posts every day. | 1st Dec | 25th Dec | |
| Advent of Svelte 2025 | 24 days of Svelte knowledge, tips, and insights to unwrap. | 1st Dec | 24th Dec | |
| CSS Advent Calendar 2025 | Highlighting a new CSS feature or property | 1st Dec | 24th Dec | |
| F# Advent Calendar 2025 | Daily blog posts related to F# stories, experiences and their unbribled passion for F#. | 1st Dec | 24th Dec | |
| JVM Programming Advent Calendar 2025 | Daily blog posts covering various JVM-related topics. | 1st Dec | 24th Dec |
Previous years2012-2024 |
| Raku(Perl 6) Advent Calendar 2025 | One article on Raku per day, until Christmas. | 1st Dec | 25th Dec | |
| Accessibility Advent Calendar 2025 | A Japanese advent calendar for various accessibility, including web accessibility. | 1st Dec | 25th Dec |
Previous years2013-2024 |
| SelfHTML Advent Calendar 2025 | Tips and Tricks for Web, submitted and curated by the community members. | 1st Dec | 25th Dec | |
| 24 Days in Umbraco | Articles dedicated to Umbraco CMS | 1st Dec | 25th Dec |
Previous years2012-2024 |
| eazyBI Advent Calendar | Discover a helpful tip from the eazyBI team everyday. | 1st Dec | 24th Dec | - |
| 2025 IndieWeb Gift Calendar | Tips and Articles to improve IndieWeb Experience | 1st Dec | 25th Dec |