Claude Code vs Mellum by JetBrains: How They Actually Differ
Claude Code is the pick for terminal-first developers who want an agent that edits files, runs commands, and ships pull requests on Anthropic Claude models. Mellum by JetBrains suits developers already inside JetBrains IDEs who want fast inline code completion from an open-source model.
Compiled 2026-09-01 from our catalogue entries for Claude Code and Mellum by JetBrains.
The short answer
- Pick Claude Code if
- You want a terminal-based coding agent that edits files, executes commands, and ships PRs using Claude Opus, Sonnet, or Haiku, and you want to encode your own workflow with skills, hooks, and slash commands.
- Pick Mellum by JetBrains if
- You work primarily inside a JetBrains IDE and want fast, low-latency inline code completion from an open-source model released on Hugging Face.
- Cheapest way in
- Claude Code has a Free plan at $0; Mellum by JetBrains has no recorded pricing or plans on file.
- What we could not compare
- Mellum's platforms, pricing model, and verified plans are not recorded, so direct comparison on those is not possible.
These two tools sit in the same category, AI Coding Agents, but they solve different problems. Claude Code is Anthropic's official command-line agent that runs in the terminal, edits files, executes commands, and ships pull requests. Mellum by JetBrains is an open-source code language model built for one thing: low-latency code completion inside IDE workflows.
The practical split is between agent-style action and inline completion. Claude Code is for developers who want an agent that acts on their behalf in a terminal session and stays inside the Anthropic model family. Mellum is for developers who want the model to keep up with their typing inside a JetBrains IDE without leaving the editor.
Side by side
Every cell is a field on our catalogue entry for that tool, copied as recorded. Rows where the two differ come first; blank fields say so rather than being filled in.
| Claude Code | Mellum by JetBrains | |
|---|---|---|
| Pricing model | Paid | Not recorded |
| Starts at | Free — $0 | Not recorded |
| Runs on | web, mac, win, linux, cli, vscode-ext, jetbrains-plugin | Not recorded |
| Category | AI Coding Agents | AI Coding Agents |
| Public source code | No public repo listed | No public repo listed |
| Public docs | Not listed | Not listed |
- Public source code: From the repository link on each catalogue entry, not a licence audit.
Where Claude Code is the better fit
- First-class support for Anthropic Claude Opus, Sonnet, and Haiku.
- Native MCP server protocol support as both client and server.
- Skills, hooks, and slash commands let teams encode their own workflow primitives.
Where Mellum by JetBrains is the better fit
- Open-source code language model released by JetBrains on Hugging Face.
- Purpose-built for low-latency code completion in IDE workflows.
- Integrates with JetBrains IDEs through the JetBrains AI Assistant plugin.
Which one should you pick?
It is built around terminal-first agent workflows, supports Claude Opus, Sonnet, and Haiku, and offers a Free plan at $0 to get started.
It is purpose-built for low-latency code completion and is delivered to JetBrains IDEs through the JetBrains AI Assistant plugin.
Skills, hooks, and slash commands let teams encode workflow primitives, and the Max plans start from $100 / month for higher usage.
Frequently asked questions
- Does Claude Code work outside the terminal?
- The fact sheet lists platforms including web, mac, win, linux, cli, vscode-ext, and jetbrains-plugin in addition to the CLI.
- Is Mellum a full agent like Claude Code?
- No. The fact sheet states Mellum is focused on code completion rather than broader agentic coding tasks, and that its capability breadth is narrower than larger frontier code models.
- Can Mellum be used outside JetBrains IDEs?
- The fact sheet only records integration with JetBrains IDEs through the JetBrains AI Assistant plugin; other platforms are not recorded.
- Can Claude Code use GPT or Gemini models?
- The fact sheet states it is locked to Anthropic models with no GPT or Gemini support out of the box.
- How much does Mellum cost?
- Pricing model, starting price, and verified plans are all not recorded on our fact sheet, so we cannot quote them.
What we compared
This page states nothing that is not in the two catalogue entries below. The exact text used to write it is reproduced here so you can check our reading, and both tools link through to their own pages and to the vendor.
- /tools/claude-code — checked 2026-05-25 · official site
- /tools/mellum-by-jetbrains — checked 2026-06-21 · official site
Show the source text
## Claude Code (/tools/claude-code) Tagline: Anthropic's official CLI agent for Claude — runs in the terminal, edits files, executes commands, and ships PRs. Category: AI Coding Agents Pricing model: paid Starts at: Free — $0 Platforms: web, mac, win, linux, cli, vscode-ext, jetbrains-plugin Public repo: none listed Docs: none listed Verified plans (read 2026-08-24): Free $0 | Pro $17 / month with annual subscription discount, or $20 if billed monthly | Max (5x or 20x) From $100 / month Strengths on file: First-class support for Anthropic Claude Opus, Sonnet, and Haiku.; MCP server protocol is natively supported as both client and server.; Skills, hooks, and slash commands let teams encode workflow primitives. Limits on file: Locked to Anthropic models — no GPT or Gemini support out of the box.; Terminal-first UX has a learning curve for developers expecting an IDE. Claude Code is Anthropic's official command-line agent for Claude — it runs in the terminal, edits files, executes commands, and ships pull requests. Its strength is depth on Claude and extensibility: first-class support for Opus, Sonnet, and Haiku, native MCP as both client and server, and skills, hooks, and slash commands that let teams encode their own workflow primitives. It's for developers comfortable in the terminal who want an agent that acts, not just autocompletes. Two trade-offs: it's locked to Anthropic models — no GPT or Gemini out of the box — and the terminal-first UX has a learning curve if you're expecting an IDE. In the stack it's the terminal-first agent next to IDE-native Cursor and the open, model-agnostic Aider. ## Mellum by JetBrains (/tools/mellum-by-jetbrains) Tagline: Fast LLMs for low-latency and high-performance workflows Category: AI Coding Agents Pricing model: not recorded Starts at: Not recorded Platforms: not recorded Public repo: none listed Docs: none listed Verified plans: none on file Strengths on file: Mellum is an open-source code language model released by JetBrains on Hugging Face.; It is purpose-built for low-latency code completion in IDE workflows.; It integrates with JetBrains IDEs through the JetBrains AI Assistant plugin. Limits on file: It is focused on code completion rather than broader agentic coding tasks.; Its capability breadth is narrower than larger frontier code models. Mellum by JetBrains is an open-source code language model, released by JetBrains on Hugging Face, built for low-latency code completion in IDE workflows. It is purpose-built for low-latency completion rather than general chat, and it integrates with JetBrains IDEs through the JetBrains AI Assistant plugin. It fits developers already in JetBrains IDEs who want fast inline completion. It is not aimed at broader agentic coding, since it targets completion rather than agent tasks, and its capability breadth is narrower than larger frontier code models.
Change log
- 2026-09-01 — First published, compiled from the catalogue entries for Claude Code and Mellum by JetBrains.