What changes in this tool
Render common Markdown headings, lists and emphasis as HTML. Parses a documented input subset and writes the corresponding output representation. Markdown headings, paragraphs, bullet lists, emphasis, fenced code and basic links become HTML text. Raw HTML in the input is escaped, which avoids executing it in the output. Compare the rendered article if the source uses custom extensions or nested structures.
Know the format
Markdown is a family of lightweight writing conventions; CommonMark defines one carefully specified core. This local converter handles headings, paragraphs, unordered lists, fenced code, strong or emphasized text, inline code and basic web links. Raw HTML in Markdown is escaped rather than executed. The reverse conversion accepts a small set of semantic HTML tags and rejects unfamiliar elements instead of silently dropping content. Complex tables, nested lists, images, custom extensions and CSS have no complete round trip here. Because HTML can encode presentation and structure that Markdown cannot express, compare the rendered result as well as the underlying text after conversion.
A dependable workflow
A change of data format is a mapping between two information models, not merely a change of punctuation. Begin with a tiny representative record that includes a non-ASCII value, a missing field or a nested value when relevant. Run the conversion and inspect how keys, ordering, numbers, null values, arrays and repeated items appear. Some target formats have no native equivalent for a source feature; the individual guide states the supported mapping. Feed the result to the intended receiver and, if possible, convert it back to compare the meaningful fields. For a bulk migration or an external contract, use a full parser and a schema test, because a plausible-looking sample does not establish complete interoperability.
Check the result
Keep the original next to the output and test a small known example before handling a large document. Compare meaningful content, not only file size or the number of lines. Check names, quoted strings, non-ASCII characters, line endings and any repeated fields after the transformation. A syntactically readable result does not validate a schema, prove that code executes, or establish that data is safe to publish. This site processes the entered text in the browser and displays the result as text, but the copy you paste into another application will follow that application’s rules. If the tool rejects an input, do not remove unexplained characters merely to get an output: identify which construct is outside the supported subset and use a dedicated parser when necessary.