A pastebin for ideas, diagrams, screenshots, GIFs and mood boards — free, no signup. Paste images, text and Mermaid onto one board, draw arrows and notes on top, and share a single link. Everyone who opens it sees the same board, live.
Open cnvs.app and you get a fresh board with its own URL — https://cnvs.app/#<id>. That URL is your paste. Press Ctrl/⌘+V or drag and drop to put things on it:
Instead of a bare file, the person you send it to gets the image with its context: the arrows, the notes, the diagram next to it.
An AI agent can create a board with content in one call — the MCP create_board tool or REST POST /api/boards with content — and hand you the link. Notes, Mermaid diagrams and drawings land on a live board you can open, edit and pass on. See Developers and AI whiteboard.
| Capability | Pastebin | mermaid.live | Imgur | cnvs.app |
|---|---|---|---|---|
| What you share | Text / code paste | Mermaid diagram (encoded in the link) | Images & GIFs, with direct links | A live board: images, text, diagrams, drawings |
| Images & GIFs | No | No | Yes | Yes — PNG, JPEG, WebP, GIF, SVG |
| Mermaid rendering | No | Yes | No | Yes — in any text node |
| Freehand drawing & annotation | No | No | No | Yes — ink, lines, arrows, boxes |
| Real-time collaboration | No | No | No | Yes — everyone with the link, live |
| AI agent API (MCP) | — | — | — | Yes — https://cnvs.app/mcp and REST |
| Direct file link | Raw text link | — | Yes | No — you share the board |
| Signup required to create | Varies | No | Varies | No |
| Expiry | Varies | — | Varies | 30 days without being opened |
Yes. Open cnvs.app and you get a fresh board with its own URL — no account, no email, no paywall. Paste or drop your content and send the board URL (https://cnvs.app/#<id>); that link is the paste.
PNG, JPEG, WebP, GIF and SVG. Animated GIFs and SVGs are kept as-is, up to about 900 kB each. Other raster images pasted in the browser are downscaled to 800 px on the long edge and re-encoded as WebP, so cnvs.app is for sharing screenshots and references in context, not for full-resolution photo hosting.
No. Only image payloads are accepted — the server checks the payload's leading bytes are PNG, JPEG, GIF, WebP or SVG (a header check, not a full decode), not just the label — so ordinary PDFs, archives, documents and other files are rejected. For text and code, paste it as a text note; for diagrams, paste Mermaid source.
A board is deleted automatically after 30 days without being opened. Opening the board in a browser resets the clock, as does a full board read through the REST API or the MCP get_board tool. Deleted boards cannot be recovered, so save a .json copy if you need one. Details are on the pricing page.
No. There is no hotlinkable URL for a single image file — the board is the unit you share. That is the point: the image arrives with its context, so you can put arrows, notes and other screenshots around it instead of sending a bare file.
Yes. Lock the board with a short access key (PIN) from the padlock in the toolbar. A write-lock keeps the board public to view while only key-holders can edit; a full lock also hides it from anyone without the key.
Yes. An AI agent can create a board with content in one call — the MCP create_board tool or REST POST /api/boards with content — and hand you the link. It is a pastebin your AI can paste into: notes, Mermaid diagrams and drawings land on a live board you can open and edit.