Mellum Models by JetBrains

JetBrainsApache 2.0Open source

1 model2025Up to 8k ctx

Last refreshed 2026-06-29. Next refresh: weekly.

Details

ResearcherJetBrains

LicenseApache 2.0OSI-approved

Commercial useCommercial use: permitted

Models1

Released2025

Max context8k

Links

Website HuggingFace

About

Mellum is JetBrains' open-weights 4B code-completion model family, trained from scratch for professional developer tooling and optimized for IDE code suggestions.

Decision facts

Best fit: codecoding
Capability starting point: Mellum 4B with 8k context
Lowest tracked input: Not tracked
Closest related family: Mellum 2

Current Variants

Use-when guidance is based on each model's tracked capabilities, context window, release date, and replacement status.

1 in view

Mellum 4BCurrent

Use when the workload needs code, 8k context, and 4B parameters.

2025-04code8k context4B parameters

Current Mellum variants with use-when guidance and lifecycle status
Model	Use when	Released	Signals	Status
Mellum 4B	Use when the workload needs code, 8k context, and 4B parameters.	2025-04	code8k context4B parameters	Current

Release Timeline

1 release group

2025-04

1 current

Mellum 4B

code8k context4B parameters

Current

Specifications(1 models)

Mellum model specifications comparison
Model	Released	Context	Parameters
Mellum 4B	2025-04	8k	4B

Models(1)