diagrams.net
diagrams.net
Full diagram editor that works without an account or a saved file
No sign-upOn deviceClassic
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asciiflow.com
Draws boxes and arrows as plain ASCII you can paste into a comment.
A grid canvas where you drag boxes, lines and arrows and the output is monospaced text characters. That makes it the right answer whenever the diagram has to live somewhere images cannot go — a code comment, a commit message, a README rendered in a terminal, an RFC. Everything runs locally and drawings persist in the browser. It is deliberately crude: no colour, no curves, and the result depends on the reader using a monospaced font.
Questions
Works the moment the page loads. No account, no email, no trial. Output is monospaced characters only, and it breaks visually for anyone reading in a proportional font.
No. ASCIIFlow does the work inside your browser, so the file never leaves your device — you can load the page, disconnect from the network, and it still works. That makes it a reasonable choice for material containing personal data.
Output is monospaced characters only, and it breaks visually for anyone reading in a proportional font.
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Same category or same task, ordered by how closely they overlap.
diagrams.net
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