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NEWOrchestrate Claude Code, Codex and Warp Agent in Studio

Your own ChatGPT.Private, offline, yours.

Langtrain turns open-source models like Llama, Qwen and Mistral into an AI assistant trained on your company's data. It runs on your own hardware, even with no internet, and the weights are yours to keep.

Start training freeSee how it works
  • Runs fully offline
  • You own the model weights
  • Works with the OpenAI SDK
  • No ML team needed
trainingllama-3.1-8bLoRA · r=16
EXAMPLE RUN
TRAIN LOSS
0.590
STEP
0520 / 1200
EPOCH
1.30 / 3
  1. step 0050loss 1.648 lr 2.0e-4
  2. step 0100loss 1.403 lr 2.0e-4
  3. step 0150loss 1.207 lr 1.9e-4
  4. step 0200loss 1.083 lr 1.9e-4
  5. step 0250loss 1.007 lr 1.8e-4
  6. step 0300loss 0.920 lr 1.7e-4
  7. step 0350loss 0.802 lr 1.6e-4
  8. step 0400loss 0.693 lr 1.5e-4
  9. step 0450loss 0.631 lr 1.4e-4
  10. step 0500loss 0.599 lr 1.3e-4
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Langtrain

The fine-tuning platform for production LLMs.
Built for builders who demand sovereignty.

  • Github
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  • Fine-Tuning
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  • Pricing
  • Enterprise

Use Cases

  • Customer Support AI
  • Internal Code Assistants
  • Healthcare & HIPAA
  • Financial Services
  • Legal Document QA
  • E-Commerce & Retail
  • Education & EdTech
  • Manufacturing
  • Research & Data Teams
  • All Use Cases

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  • Documentation
  • Quick Start
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Langtrain

© 2026 QUADTREE AI TECHNOLOGIES PRIVATE LIMITED. Langtrain is a product of QUADTREE AI TECHNOLOGIES PRIVATE LIMITED.

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  • Made with ♥love in India

Why Langtrain

Why not just use ChatGPT or Claude? Because it isn't yours.

Hosted assistants are a good start. They stop working for you the moment your data is sensitive, your domain is specialised, or your costs have to be predictable.

  • Your data leaves the building

    Every prompt, document and customer record you paste in is sent to someone else's servers.

    LANGTRAINA Langtrain model runs where your data already is. Nothing is sent out.

  • It doesn't know your business

    General models learned the internet, not your products, policies, tickets or tone of voice.

    LANGTRAINFine-tuned on your own documents and conversations, it answers the way your team would.

  • You rent it forever

    You pay per token for as long as you use it, and the model can change or be retired without asking you.

    LANGTRAINYou keep the weights. Self-hosted, there are no per-token fees and the model only changes when you retrain it.

  • It needs the internet

    No connection, no assistant: not on a plane, a factory floor or a locked-down network.

    LANGTRAINExport to GGUF and run it with llama.cpp on a laptop or server that never goes online.

How it works

Five steps to your own AI. No ML team required.

Upload what your team already has: help articles, tickets, chats, documents. Langtrain turns it into training data, trains an open model on it, checks it, and hands it back to run wherever you want.

Read the quick start
  1. 01DataUpload chat-format JSONL. One conversation per line.
  2. 02TrainLoRA, QLoRA, SFT, full fine-tuning or RLHF.
  3. 03EvaluateScore the fine-tune on held-out data before it ships.
  4. 04DeployLangtrain Cloud, Docker, or Kubernetes with the Helm chart.
  5. 05APICall it like any OpenAI-compatible model.

Open models, trained with our recipe. The hard parts are handled.

A base model like Llama or Qwen is a generalist. Our training pipeline makes it a specialist in your business: memory-efficient fine-tuning so big models fit small GPUs, preference tuning so it sounds like you, and automatic search so the settings are right the first time.

  • 01 / METHOD

    LoRA and QLoRA

    Train small adapter matrices instead of the whole model. QLoRA loads the base model in 4-bit NF4 so larger models fit on smaller GPUs.

    quantization: nf4Read the guide
  • 02 / METHOD

    Supervised fine-tuning

    Teach the model your task from chat-format examples, with loss masked to the turns it should learn.

    {"messages": [...]}Read the guide
  • 03 / METHOD

    Full fine-tuning

    Update every weight for deeper domain adaptation, with DeepSpeed for multi-GPU memory efficiency.

    deepspeed_stage: 2Read the guide
  • 04 / METHOD

    Preference tuning

    Make it answer the way your team would: DPO learns directly from pairs of better and worse answers; RLHF trains a reward model and optimises against it with PPO.

    DPO · RLHF (PPO)Read the guide
  • 05 / METHOD

    Automatic tuning

    Learning rate, rank, batch size and epochs are searched for you with Bayesian optimisation, so you don't tune by hand.

    search: bayesianRead the guide

Runs offline

Your data never leaves. Neither does your model.

Training runs in an isolated environment with no inbound traffic. The result is a file you own: run it offline on a laptop, on your own servers, in your cluster, or on our cloud.

INBOUNDISOLATED VPCNO INGRESSEPHEMERAL INSTANCEyour database modelweightsout to you

Training runs on dedicated, ephemeral instances in an isolated VPC with no ingress routing.

Isolated compute

Langtrain Cloud

Push the trained model with one command. It becomes available through the OpenAI-compatible API.

$ trainer.push("my-assistant")
Interface
OpenAI-compatible API
Deploy
One command
Deployment docs

Models

Start from open models. Leave with your own.

Browse the model hub
  • MELLaMA 3.3 70B70B
  • MELLaMA 3.2 90B Vision90B
  • MELLaMA 3.2 3B3B
  • MELLaMA 3.1 405B405B
  • MIMistral Large 2123B
  • MICodestral 22B22B
  • MELLaMA 3.3 70B70B
  • MELLaMA 3.2 90B Vision90B
  • MELLaMA 3.2 3B3B
  • MELLaMA 3.1 405B405B
  • MIMistral Large 2123B
  • MICodestral 22B22B
  • GOGemma 2 27B27B
  • GOGemma 2 9B9B
  • ALQwen 2.5 72B72B
  • ALQwen 2.5 Coder 32B32B
  • DEDeepSeek V3671B
  • MIPhi 3.5 Mini3.8B
  • GOGemma 2 27B27B
  • GOGemma 2 9B9B
  • ALQwen 2.5 72B72B
  • ALQwen 2.5 Coder 32B32B
  • DEDeepSeek V3671B
  • MIPhi 3.5 Mini3.8B

Use cases

Built for teams whose data can't leave. One platform, every department.

All use cases
  • Customer Support AIAnswers from your help centre and past tickets, in your tone.
  • Internal Code AssistantsA coding assistant trained on your private repositories.
  • Healthcare & HIPAAClinical text processed inside your own environment.
  • Financial Services AIFilings, reports and client data analysed in-house.
  • Legal Document QAPrivileged documents searched without any outside API.
  • E-Commerce & RetailProduct and order questions answered in your brand's voice.
  • Education & EdTechTutors trained on your own course material.
  • Manufacturing & IndustrialManuals and maintenance logs, answered on the shop floor.
  • Research & Data TeamsFine-tunes you can reproduce, compare and defend.

Compare

The control of building it yourself. The ease of an API.

Langtrain compared with hosted AI APIs and building your own stack
CapabilityLangtrainChatGPT / Claude APIsBuild it yourself
Runs on your own hardwareYesNoYes
Works with no internetYesNoYes
You own the model weightsYesNoYes
Trained on your company's dataYesLimitedYes
No ML team or GPU cluster to runYesYesNo
OpenAI-compatible APIYesTheir ownYou build it
How you payFree to start, then a planPer token, for as long as you use itGPUs and engineers

Hosted APIs change their offerings often; check their current terms.

Products

A desktop app, an SDK, a CLI and an API. Use whichever suits your team.

  • StudioDesktop app for preparing datasets and running fine-tunes locally or on managed GPUs.macOS · Windows · Linux
  • SDKPython and Node client libraries to start runs from your scripts and notebooks.Python · Node
  • CLITrain, export and deploy from the terminal or a CI job.Terminal · CI
  • APIREST API with OpenAI-compatible endpoints for the models you deploy.OpenAI-compatible

In code

Prefer code? The same five steps, in Python.

Every snippet is copied from the docs, so what you see is what you run.

training_data.jsonl
from /docs/quick-start
1
2
{"messages": [{"role": "user", "content": "What is Langtrain?"}, {"role": "assistant", "content": "It's a platform for fine-tuning LLMs."}]}
{"messages": [{"role": "user", "content": "How do I start?"}, {"role": "assistant", "content": "Use the LoRATrainer class!"}]}

Pricing

Start free. Pay as your model earns its keep.

Compare plans
  • Starter

    Your first private model.

    $0forever

    • 5M training tokens
    • Langtrain Studio (desktop)
    • You own the weights
    Start training free
  • Pro

    For teams training and serving models.

    $20per month · ₹1,499 in India

    • 10 agents
    • Langtrain Studio Pro
    • 200M training tokens
    • Browser agent sessions
    See Pro
  • Enterprise

    For data that must stay in your environment.

    Customannual agreement

    • VPC and on-premise deployment
    • Dedicated GPU clusters
    • SSO and audit logs
    Talk to us

FAQ

Before you start. Straight answers.

More answers in the full FAQ.

Stop renting AI. Own it.

$pip install langtrain-ai

Train your first private model free. Keep the weights, run it anywhere, and never send your data to someone else's AI again.

Start training freeRead the quick start