LLM Reference

Mellum 4B

Researched today

Last refreshed 2026-06-01. Next refresh: weekly.

Open SourceCoding

Mellum 4B has model metadata, but missing tracked provider pricing keeps it from being a default production pick.

Decision context: Coding task fit, 0 tracked provider routes, and research from 2026-06-01.

Use it for

  • Teams evaluating coding
  • Workloads that can use a 8k context window

Do not use it for

  • Cost-sensitive launches that need sourced token pricing
  • Vision or document-understanding workloads
  • Strict JSON or tool-calling flows

Cheapest output

-

No tracked output price

Provider routes

0

No provider route in seed

Quality / dollar

Unknown

No task benchmark coverage yet

Freshness

2026-06-01

Researched today

fresh

Top use-case fit

Coding

Included by capability and metadata signals in the decision map.

Provider price ladder

No tracked provider token pricing is available for this model yet.

Benchmark peer barsfor Coding

No task-mapped benchmark peers are available for this model yet.

Migration checks

No linked migration route is available for this model yet.

About

Mellum 4B is JetBrains' open-weights LLaMA-style code-completion model trained on roughly 4.2T tokens across permissively licensed code and Wikipedia. It is optimized for IDE code suggestions and local or self-hosted developer tooling.

Mellum 4B has a 8k-token context window.

Capabilities

No model capability flags are currently sourced.

Rankings

Specifications

FamilyMellum
Released2025-04-30
Parameters4B
Context8k
ArchitectureDecoder Only
Specializationcode
LicenseApache 2.0
Trainingpretrained

Created by

Developer tools company building code-specialized Mellum models.

Prague, Czech Republic
Founded 2000
Website