Tinker - Thinking Machines Lab

Tinker is a training API for developers

Control every aspect of model training and fine-tuning while we handle the infrastructure.

Your ideas in four functions

forward_backward

Perform a forward pass and a backward pass, accumulating the gradient.

optim_step

Update weights based on the accumulated gradient.

sample

Generate tokens for interaction, evaluation, or RL actions.

save_state

Save training progress for resumption.

Supported models

THINKING MACHINES](/content/inkling/index.html)

Inkling NEW

MoE

Inkling-SmallCOMING SOON

MoE

DEEPSEEK](https://huggingface.co/deepseek-ai)

DeepSeek-V3.1

MoE

MOONSHOT](https://huggingface.co/moonshotai)

Kimi-K2.6

MoE

NVIDIA](https://huggingface.co/nvidia)

Nemotron-3-Nano-30B-A3B-BF16

MoE

Nemotron-3-Super-120B-A12B-BF16

MoE

Nemotron-3-Ultra-550B-A55B-BF16

MoE

GPT-OSS](https://huggingface.co/collections/openai/gpt-oss)

GPT-OSS-120B

MoE

GPT-OSS-20B

MoE

QWEN](https://huggingface.co/Qwen)

Qwen3.6-35B-A3B

MoE

Qwen3.6-27B

Dense

Qwen3.5-4B

Dense

Qwen3.5-9B

Dense

Qwen3.5-9B-Base

Dense

Qwen3.5-35B-A3B-Base

MoE

Qwen3.5-397B-A17B

MoE

Qwen3-8B

Dense

Tinker uses LoRA

LoRA fine-tunes models by training a small add-on instead of changing all the original weights.

Read blog post

Tinker cookbook

Explore realistic examples and common abstractions for fine-tuning language models with the Tinker API.

View cookbook

Tinker lets researchers focus on datasets, algorithms, and environments without the complexities of compute and infrastructure.

Tyler Griggs

Tinker lets us focus on the research, rather than spending time on engineering overhead. That's something no amount of raw GPU credits can substitute.

Ziran Yang, Yong Lin, Chi Jin

The training infrastructure has been abstracted away, which makes focusing on our data and evals far easier. Tinker has made it easy to jump into RL work.

Jason Liu

Tinker has been reliable for quickly iterating without worrying about hardware or infrastructure.

Eric Gan

FAQs

How do I access Tinker?

Join here. If you're a university or organization looking for wide scale access, contact tinker@thinkingmachines.ai.

What is Tinker and who is it for?

Tinker is a flexible API for efficiently fine-tuning open source models with LoRA. It's designed for researchers and developers who want flexibility and full control of their data and algorithms without worrying about infrastructure management.

What is LoRA and why does Tinker use it?

LoRA is an efficient approach to fine-tuning that trains a streamlined adapter instead of updating all base model weights. Our research demonstrates that with the right setup, LoRA matches the learning performance of full fine-tuning while providing more flexibility and requiring less compute.

Do I need to manage training infrastructure?

Tinker handles scheduling, tuning, resource management, and infrastructure reliability so you can focus on the training data and algorithms. Behind the scenes, Tinker orchestrates distributed training on powerful GPU clusters for efficient utilization.

What do I need to start training?

A dataset of supervised learning examples or reinforcement learning environments. After picking a base model to train on, the Tinker API provides simple functions to compute gradients, update the weights, and sample outputs from the trained model. See our cookbook for examples to get started.

What models can I train with Tinker?

Tinker is currently available for a broad selection of open-source models, ranging from compact models like Qwen3.5-4B to large MoEs like Kimi-K2.6. We plan to expand our model lineup with even more choices soon.

How do you handle my training data?

Your data is used solely to fine-tune your models. We do not use your data to train our own models.

Can I download my model weights?

Yes, we have an API endpoint that lets you download any checkpoint you've saved.

How do I stay up to date with Tinker news?

Follow Tinker on X for API updates, new model and feature announcements, and weekly roundups of featured projects from the Tinker community.

How much do I have to pay to use Tinker?

Tinker uses a pricing plan that reflects usage. All prices are in USD per million tokens. See pricing in our docs. Checkpoint storage is charged at $0.10/GB-month.