DeepSeek

Overview

DeepSeek is a Chinese AI lab that burst into the global conversation with open-weight reasoning models — most famously the R1 series that performs chain-of-thought math and coding at a level previously associated only with closed frontier labs. It offers both a free web chat at https://deepseek.com and an API priced dramatically below Western rivals, and it publishes model weights so anyone can self-host. For developers and researchers, that combination — frontier-level reasoning, open weights, rock-bottom price — is the whole story.

What makes DeepSeek matter is that it broke the assumption that top-tier reasoning must be locked behind a paywall and a black box. In our evaluation the R1 model genuinely rivals ChatGPT and Claude on hard SQL, algorithm, and proof-style questions, and because the weights are open you can run a distilled version locally for privacy or cost control. It is the model we reach for when a closed assistant hedges on a difficult technical problem.

The caveats our evaluation notes are real but bounded. DeepSeek applies censorship on some political topics, which matters if your work touches sensitive subjects. Its hosted service also occasionally overloads at peak, returning slow or failed responses. For most technical users these are acceptable trade-offs against the price and openness, but they are worth knowing before you depend on it for production.

Key Features

• Frontier-level reasoning at low cost — The R1 series does explicit chain-of-thought reasoning that competes with closed models on math and code benchmarks, at a fraction of the price. This matters because hard reasoning used to mean an expensive API call.
• Open weights (R1/V3) — You can download and self-host the models, which is rare among top performers. For teams with privacy or sovereignty requirements, that openness is the decisive feature.
• Strong coding and math — DeepSeek consistently posts competitive scores on programming and quantitative benchmarks, making it a dependable engine for technical tasks rather than just a chat toy.
• Very low API pricing — Tokens cost a small fraction of Western frontier APIs, so batch reasoning and high-volume use stay affordable. This is why it is a developer favorite for cost-sensitive pipelines.
• Free web chat — The hosted chat gives anyone access to the reasoning models without setup, a gentle on-ramp to capabilities that used to require a paid plan.
• Distilled models for local use — Smaller distilled versions run on modest hardware via tools like lm-studio, extending privacy and offline access.

Pricing

In our evaluation the free web chat is the obvious starting point and is genuinely capable for technical questions. The API is where DeepSeek shines for builders: at its low per-token price, running large volumes of reasoning is affordable in a way closed competitors are not. There is no paid “Pro” chat tier to weigh — you either use free chat or pay per token on the API, which keeps the decision simple. If you need privacy or offline use, self-hosting the open weights costs only your compute.

How It Compares

vs. ChatGPT: ChatGPT offers a far larger ecosystem, better UX, and more features, while our evaluation finds DeepSeek matching or beating it on hard reasoning and costing a fraction. Choose ChatGPT for breadth and polish; choose DeepSeek for cheap, open, strong technical reasoning.

vs. Claude: Claude writes more naturally and is the better general assistant, but DeepSeek’s R1 is excellent on math and code and is open-weight. For developers who want to self-host or batch-reason cheaply, DeepSeek wins; for prose and safety defaults, Claude.

vs. lm-studio: lm-studio is a desktop app for running local models, including DeepSeek distills, whereas DeepSeek is the model provider. They pair naturally: use DeepSeek’s weights inside lm-studio for a private, offline chat.

Getting Started

• Open https://deepseek.com and start chatting for free — no credit card needed to try the reasoning models.
• Toggle the reasoning model (R1) for hard problems — ordinary chat is fine for casual text, but switch to R1 for math, proofs, and tricky code.
• Get an API key from the platform if you want to automate; the docs show standard OpenAI-style calls, so migration is easy.
• Try self-hosting a distilled model via lm-studio if privacy or offline use matters to you.
• Avoid the beginner mistake of expecting unfiltered answers on sensitive topics — censorship exists, so route those questions elsewhere.
• Expect peak-time slowness on the free tier — for reliable throughput, the API or a local instance is steadier.
• Power-user tip: pair DeepSeek’s API with an editor like Cursor for in-editor solves; the low price makes always-on reasoning affordable.

Hands-on Verdict

DeepSeek is the open-weight reasoning challenger — the R1 model does chain-of-thought math and coding that rivals closed labs, and it is free to run locally. In our evaluation it is the model we use for hard SQL and algorithm questions where ChatGPT hedges, and the chat UX, while plainer than Claude, is perfectly usable.

Who should use it: developers, researchers, and cost-sensitive builders who want strong reasoning without a paywall or a black box. Who should skip it: users who need unfiltered answers on sensitive topics, a polished consumer app, or the broadest ecosystem (use ChatGPT). Practical tip: self-host a 7B or 70B distill for privacy, or use the API for batch reasoning — and pair it with Cursor for in-editor problem solving.