AI Desk · Model Identity · Compare
DeepSeek: DeepSeek V4 Flash 0423 · DeepSeek: DeepSeek V4 Pro 0813
Identity similarity: very highExact tokenizer agreement · 50/50Exact agreement across every measured string is strong evidence of shared tokenizer lineage. It shows shared ancestry, and does not on its own establish that these are the same release.
DeepSeek: DeepSeek V4 Flash 0423 recordDeepSeek: DeepSeek V4 Pro 0813 recordOpen in the interactive bench
Tokenizer fingerprint
50 of 50 mutually clean strings agree| Test string | DeepSeek: DeepSeek V4 Flash 0423 | DeepSeek: DeepSeek V4 Pro 0813 | Verdict |
|---|---|---|---|
| en-prose | 14 | 14 | match |
| en-long | 16 | 16 | match |
| spaces-20 | 3 | 3 | match |
| spaces-60 | 3 | 3 | match |
| tabs-20 | 4 | 4 | match |
| newlines-20 | 4 | 4 | match |
| mixed-ws | 7 | 7 | match |
| digits-9 | 3 | 3 | match |
| digits-12 | 4 | 4 | match |
| digits-30 | 10 | 10 | match |
| digits-sep | 7 | 7 | match |
| float-long | 9 | 9 | match |
| zh-common | 9 | 9 | match |
| zh-long | 10 | 10 | match |
| zh-rare | 18 | 18 | match |
| ja-kana | 9 | 9 | match |
| ja-kanji | 11 | 11 | match |
| ko | 13 | 13 | match |
| ru | 13 | 13 | match |
| ar | 10 | 10 | match |
| he | 14 | 14 | match |
| hi | 18 | 18 | match |
| th | 11 | 11 | match |
| el | 16 | 16 | match |
| emoji-basic | 10 | 10 | match |
| emoji-skin | 14 | 14 | match |
| emoji-zwj-family | 11 | 11 | match |
| emoji-zwj-x3 | 33 | 33 | match |
| emoji-flags | 16 | 16 | match |
| emoji-prof | 19 | 19 | match |
| math | 22 | 22 | match |
| boxdraw | 27 | 27 | match |
| combining | 10 | 10 | match |
| cjk-ext-b | 16 | 16 | match |
| surrogates | 33 | 33 | match |
| zalgo | 36 | 36 | match |
| rtl-mix | 6 | 6 | match |
| py-code | 25 | 25 | match |
| py-indent | 15 | 15 | match |
| json | 20 | 20 | match |
| html | 16 | 16 | match |
| regex | 47 | 47 | match |
| camel | 7 | 7 | match |
| snake | 8 | 8 | match |
| rare-word-x5 | 26 | 26 | match |
| repeat-tok | 41 | 41 | match |
| base64 | 34 | 34 | match |
| hex | 12 | 12 | match |
| url | 17 | 17 | match |
| uuid | 27 | 27 | match |
Values are the marginal prompt-token cost of each string with the model's fixed overhead subtracted. An x marks a row excluded as corrupt for that model.
API surface
The declared serving contracts differ| Field | DeepSeek: DeepSeek V4 Flash 0423 | DeepSeek: DeepSeek V4 Pro 0813 | Verdict |
|---|---|---|---|
| Context length | 1048576 | 1048576 | ✓ match |
| Max output tokens | 384000 | – | × differs |
| Supported parameters | frequency_penalty, include_reasoning, logit_bias, logprobs, max_completion_tokens, max_tokens, min_p, presence_penalty, reasoning, reasoning_effort, repetition_penalty, response_format, seed, stop, structured_outputs, temperature, tool_choice, tools, top_a, top_k, top_logprobs, top_p | frequency_penalty, include_reasoning, logit_bias, logprobs, max_tokens, min_p, presence_penalty, reasoning, reasoning_effort, repetition_penalty, response_format, seed, stop, structured_outputs, temperature, tool_choice, tools, top_k, top_logprobs, top_p | × differs |
| Defaults | {} | {"temperature":1,"top_p":1} | × differs |
| Reasoning contract | {"mandatory":false,"supported_efforts":["xhigh","high"],"default_effort":"high"} | {"mandatory":false,"supported_efforts":["max","high","low"],"default_effort":"high"} | × differs |
| Modalities | text->text | text->text | ✓ match |
Method: tokenizer fingerprinting, v1, 50 strings. Raw data on the data page. This page is static and dated; the interactive bench compares any two of the 422 catalogue models.