markwhen.com

What It Is

Markwhen is a Markdown-like journal language. Its core idea is to record events, dates, and descriptions in text that feels close to Markdown, then have a parser convert that into JSON and ultimately render it as views such as timelines, calendars, and oneview. It is better understood as “a text format for timeline data plus a parsing and presentation ecosystem,” making it suitable for developers and knowledge-management users who want to maintain time-based information in plain text.

Core Capabilities

Based on the documentation structure and examples, Markwhen supports single dates, date ranges, multiple date formats, event descriptions, sections, tags, properties, checklists, links, time zones, recurrence rules, and Frontmatter. The example JSON includes fields such as an event tree, ISO date ranges, text ranges, collapsed-state information, and parsing messages, indicating that its parsed output is fairly structured and convenient for developers to process further. In terms of ecosystem, the documentation mentions a Parser, CLI, API, Webhooks, Embedding, RSS, a VS Code extension, and an Obsidian plugin, and it also provides the online editor at meridiem.markwhen.com.

Pricing and Deployment

The captured content does not disclose a pricing model, plans, an open-source license, or self-hosting options, so it is not possible to assess commercial cost or private-deployment feasibility. The documentation includes sections such as Data storage and privacy and Collaborative editing, but the current text does not provide specific details on privacy, storage, or collaboration policies.

Pros and Cons

Its strengths are its lightweight syntax, which naturally fits Git-based management, document embedding, and long-term maintenance. Its JSON output also makes it easier to integrate than ordinary timeline drawing tools. The VS Code and Obsidian plugins further lower the barrier to use in writing-oriented workflows. The downside is that the available information lacks details on the API, SDKs, authentication, rate limits, service support, and paid-plan boundaries; it is also unclear whether the project is open source or closed source.

Who It’s For and Access from China

Markwhen is suitable for use cases such as project roadmaps, product release plans, historical event organization, research chronologies, and personal journals, especially for teams that prefer text-based workflows. There is no evidence in the text regarding access from mainland China, so its availability there is currently unknown; payment methods are also not disclosed. If access or ecosystem support is limited, alternatives to compare include Mermaid timeline, PlantUML, TimelineJS, or timeline-related Obsidian plugins.