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2 DeepSeek models in llmwise, 2 of them in the 5 free messages you get on sign-up. DeepSeek V4.1 Flash passed 49 of 50 of our test prompts, the most of any DeepSeek model.

A real answer from our test runs

DeepSeek V4 Pro

Translate this note into German. Keep names, dates, times and room numbers exactly as they are. Team, the quarterly review with Dr. Okafor moves from Tuesday to Thursday, 16 October, at 09:15 in room B204. Please send your updated figures to Lena Brandt by Wednesday noon. The call link stays the same, and the meeting will end by 10:45 at the latest.

DeepSeek V4 Pro · passed our check · September 27, 2026

Team, das Quartalsreview mit Dr. Okafor verschiebt sich von Tuesday auf Thursday, 16 October, um 09:15 in Raum B204. Bitte sendet eure aktualisierten Zahlen bis Wednesday noon an Lena Brandt. Der Anruflink bleibt gleich, und das Meeting endet spätestens um 10:45.

Ask DeepSeek V4 Pro your own question: it's in the 5 free messages you get on sign-up, no card.

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Facts about other apps checked against App Store: DeepSeek - AI Assistant. Updated .

Short answer

DeepSeek V4.1 Flash passed the most of our test prompts, 49 of 50; DeepSeek V4 Pro 45 of 50. DeepSeek V4 Pro and DeepSeek V4.1 Flash are in the 5 free messages you get on sign-up.

The DeepSeek models in llmwise

Every DeepSeek model in llmwise: the free trial, Pro's count, a typical message at its API price, and our test results.

The DeepSeek models
ModelFree trialOn ProTypical message, API priceOur test prompts passed
DeepSeek V4 ProDeepSeekYes250 a month$0.003845 of 50 (17 of 20 hard)
DeepSeek V4.1 FlashDeepSeekYes60 a day$0.001149 of 50 (20 of 20 hard)

On Pro: the most messages a month on the model if the month goes to it alone, or a day's on an everyday model. The API price is a 4,000-token question with a 700-token answer at the model's list price as of September 2026; in llmwise you pay per message. Our tests: the 50 prompts of our test runs on September 27, 2026.

Every limit is published. Paid plans also have a monthly fair-use limit on AI cost: Pro $7.50, Max $20, Ultra $42, Studio $85. Using every message on your plan at typical sizes stays under it; very large messages and heavy research use it faster. Every limit, explained.

DeepSeek, job by job

Prompts passed on each of our 10 jobs, 5 prompts a job.

Prompts passed on each job, by model
JobDeepSeek V4 ProDeepSeek V4.1 Flash
Coding4 of 55 of 5
Writing3 of 54 of 5
Math5 of 55 of 5
Summarization4 of 55 of 5
Data analysis5 of 55 of 5
Customer support4 of 55 of 5
Translation5 of 55 of 5
SQL5 of 55 of 5
RAG and answering from documents5 of 55 of 5
Agents and tool use5 of 55 of 5

When to pick which DeepSeek model

Among the DeepSeek models only: the one that passed the most of each job, and when others tie, the one that costs less.

  • Coding

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard).

  • Writing

    DeepSeek V4.1 Flash, 4 of 5 passed (2 of 2 hard).

  • Math

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

  • Summarization

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard).

  • Data analysis

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

  • Customer support

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard).

  • Translation

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

  • SQL

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

  • RAG and answering from documents

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

  • Agents and tool use

    DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

DeepSeek on one prompt, side by side

The same hard coding prompt, “Parse CSV with quoted fields”, sent to DeepSeek V4 Pro and DeepSeek V4.1 Flash: DeepSeek V4 Pro failed and DeepSeek V4.1 Flash passed.

The prompt: Parse CSV with quoted fields (hard)
Write a JavaScript function parseCsv(text) that parses CSV text into an array of rows, each an array of strings.
- Fields are separated by commas, and rows by \n or \r\n.
- A field may be wrapped in double quotes. Inside quotes, commas and line breaks are part of the field, and "" stands for one double quote.
- A quote inside a field that doesn't start with one is an ordinary character.
- A line break at the very end of the text doesn't start a new row, and an empty string gives [].
Reply with the whole function in one ```javascript code block: plain JavaScript for Node.js 22, no imports, no TypeScript.

  • DeepSeek V4 Pro

    Failed: No answer within Pro's reply limit of 8,000 tokens: the model spent them all reasoning.

    (no reply)

    493 tokens in, 8,000 out (7,805 of them reasoning) · 69.1 s · $0.0323 · 1 message on Pro · answered by deepseek/deepseek-v4-pro-0813 via CoreWeave ·

  • DeepSeek V4.1 Flash

    Passed: All 8 tests passed.

    ```javascript
function parseCsv(text) {
  if (text === '') return [];

  const rows = [];
  let row = [];
  let field = '';
  let inQuotes = false;
  let atFieldStart = true;
  let i = 0;
  const n = text.length;

  const endField = () => {
    row.push(field);
    field = '';
    atFieldStart = true;
  };

  const endRow = () => {
    endField();
    rows.push(row);
    row = [];
  };

  while (i < n) {
    const ch = text[i];

    if (inQuotes) {
      if (ch === '"') {
        if (text[i + 1] === '"') {
          field += '"';
          i += 2;
        } else {
          inQuotes = false;
          i += 1;
        }
      } else {
        field += ch;
        i += 1;
      }
      continue;
    }

    if (ch === '"' && atFieldStart) {
      inQuotes = true;
      atFieldStart = false;
      i += 1;
      continue;
    }

    if (ch === ',') {
      endField();
      i += 1;
      continue;
    }

    if (ch === '\r' && text[i + 1] === '\n') {
      endRow();
      i += 2;
      continue;
    }

    if (ch === '\n') {
      endRow();
      i += 1;
      continue;
    }

    field += ch;
    atFieldStart = false;
    i += 1;
  }

  if (row.length > 0 || field !== '') {
    endRow();
  }

  return rows;
}
```

    522 tokens in, 1,914 out (1,537 of them reasoning) · 11.6 s · $0.0013 · 1 message on Pro · answered by deepseek/deepseek-v4.1-flash via StreamLake ·

DeepSeek's own app

llmwise isn't DeepSeek's app. DeepSeek, DeepSeek's own, has a free tier too; in its words: “Experience seamless interaction with DeepSeek's official AI assistant for free!” (App Store: DeepSeek - AI Assistant, checked ).

Where your messages go

DeepSeek models are served only through OpenRouter, by endpoints that don't store or train on prompts. The Privacy Policy has the details.

More ways to chat

The other chat pages, each with its own models and test results.

Questions

Can I chat with DeepSeek for free?

Yes, to try: DeepSeek V4 Pro and DeepSeek V4.1 Flash are in the 5 free messages you get when you sign up, once and with no card. The free-message box on this page, when it shows, is answered by GPT-6 Luna, not by DeepSeek.

Is this the official DeepSeek app?

No. llmwise isn't made by DeepSeek and isn't affiliated with it: it offers DeepSeek's DeepSeek models next to 6 other AI families, in one chat. DeepSeek's own app has a free tier too; in its words: “Experience seamless interaction with DeepSeek's official AI assistant for free!” (App Store: DeepSeek - AI Assistant, checked September 28, 2026).

Which DeepSeek model should I use?

In our test runs on September 27, 2026, DeepSeek V4.1 Flash passed the most: 49 of 50 prompts. Start on the cheaper one and switch when an answer isn't good enough: the next model sees the whole chat.

Where do my DeepSeek messages go?

DeepSeek models are served only through OpenRouter, by endpoints that don't store or train on prompts.

Claude, GPT, Gemini, DeepSeek, Grok, Kimi, and GLM, in one chat.

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