DeepSeek V3.1 Base

DeepSeek chat Free

API ID: deepseek/deepseek-v3.1-base

Input Price
Free
/1M tokens
Output Price
Free
/1M tokens

About DeepSeek V3.1 Base

This is a base model, trained only for raw next-token prediction. Unlike instruct/chat models, it has not been fine-tuned to follow user instructions. Prompts need to be written more like training text or examples rather than simple requests (e.g., “Translate the following sentence…” instead of just “Translate this”). DeepSeek-V3.1 Base is a 671B parameter open Mixture-of-Experts (MoE) language model with 37B active parameters per forward pass and a context length of 128K tokens. Trained on 14.8T tokens using FP8 mixed precision, it achieves high training efficiency and stability, with strong performance across language, reasoning, math, and coding tasks.

🏆
Price Ranking
#6 lowest price among 1240 Chat models — Top 20% cheapest!

Model Specifications

Context Length
164k
Max Output
—
Release Date
2025-08-20
Capabilities
chat
Input Modalities
text
Output Modalities
text

Best For

  • Conversations, content writing, general assistance

Consider Alternatives For

  • Image understanding (needs vision capability)
🎉

This model is completely free!

No token costs - use it without worrying about API bills.

Estimate Token Usage

DeepSeek Model Lineup

Compare all models from DeepSeek to find the best fit

Model Input Output Context Capabilities
DeepSeek V3.1 Base Current Free Free 164k chat
DeepSeek Prover V2 Free Free 164k chat
DeepSeek V3 Base Free Free 131k chat
DeepSeek V3 Base Free Free 131k chat
DeepSeek V2.5 Free Free 128k chat
DeepSeek V2.5 Free Free 128k chat

Similar Models from Other Providers

Cross-brand alternatives with similar capabilities

Google Gemma 3n 4B
Input: Free
Output: Free
Context: 33k
Alibaba Qwen Qwen2.5-VL 7B Instruct
Input: Free
Output: Free
Context: 33k
ByteDance Seedream 4.5
Input: Free
Output: Free
Context: 4k
Black Forest Labs FLUX.2 Max
Input: Free
Output: Free
Context: 47k

🚀 Quick Start

Get started with DeepSeek V3.1 Base API

OpenAI-compatible SDK
from openai import OpenAI

client = OpenAI(
    base_url="https://api.provider.com/v1",
    api_key="YOUR_API_KEY"
)

response = client.chat.completions.create(
    model="deepseek/deepseek-v3.1-base",
    messages=[
        {"role": "user", "content": "Hello!"}
    ]
)
print(response.choices[0].message.content)