DeepSeek V4 Pro Behavioral Fingerprint
How DeepSeek's DeepSeek V4 Pro answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 449 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
DeepSeek
Data generated
2026-07-08
Probe cells
15
Valid samples
449
Randomness score
34 / 100
Mean normalized entropy across cells, 0–100. 100 would be a uniform-random baseline; real models score far lower.
Signature answers
Favorite random number (1–100)
42
7 / 30 answers
Favorite color
cerulean
17 / 30 answers
Coin flip: heads
98%
Share of heads across coin-flip cells.
Answer distributions by probe cell
Empirical distributions of normalized one-word answers, per task and language. H is the Shannon entropy in bits; the uniform baseline is log2 of the answer-domain size.
Coin flip · English
n = 30 · H = 0.00 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 30 | 100.0% |
Coin flip · Chinese
n = 30 · H = 0.21 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 29 | 96.7% |
| tails | 1 | 3.3% |
Favorite number · English
n = 30 · H = 0.65 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 83.3% |
| 42 | 5 | 16.7% |
Favorite number · Chinese
n = 30 · H = 0.42 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 28 | 93.3% |
| 4 | 1 | 3.3% |
| 42 | 1 | 3.3% |
Random animal · English
n = 30 · H = 2.94 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| elephant | 13 | 43.3% |
| platypus | 3 | 10.0% |
| okapi | 2 | 6.7% |
| giraffe | 2 | 6.7% |
| dog | 2 | 6.7% |
| anteater | 1 | 3.3% |
| salamander | 1 | 3.3% |
| capybara | 1 | 3.3% |
+ 5 more answers
Random animal · Chinese
n = 30 · H = 2.94 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 企鹅 | 8 | 26.7% |
| 猫 | 6 | 20.0% |
| 大象 | 6 | 20.0% |
| 海豚 | 2 | 6.7% |
| 狗 | 2 | 6.7% |
| 鲸鱼 | 1 | 3.3% |
| 麻雀 | 1 | 3.3% |
| 袋鼠 | 1 | 3.3% |
+ 3 more answers
Random city · English
n = 30 · H = 3.42 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| london | 8 | 26.7% |
| tokyo | 4 | 13.3% |
| paris | 4 | 13.3% |
| seoul | 3 | 10.0% |
| kabul | 1 | 3.3% |
| tulsa | 1 | 3.3% |
| zurich | 1 | 3.3% |
| madrid | 1 | 3.3% |
+ 7 more answers
Random city · Chinese
n = 30 · H = 1.85 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 巴黎 | 15 | 50.0% |
| 东京 | 10 | 33.3% |
| 奥斯陆 | 1 | 3.3% |
| 卢森堡市 | 1 | 3.3% |
| 维也纳 | 1 | 3.3% |
| 伦敦 | 1 | 3.3% |
| 纽约 | 1 | 3.3% |
Random color · English
n = 30 · H = 2.05 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| cerulean | 17 | 56.7% |
| turquoise | 3 | 10.0% |
| azure | 3 | 10.0% |
| indigo | 3 | 10.0% |
| lavender | 2 | 6.7% |
| magenta | 1 | 3.3% |
| teal | 1 | 3.3% |
Random color · Chinese
n = 30 · H = 2.44 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 蔚蓝 | 13 | 43.3% |
| 靛蓝 | 8 | 26.7% |
| 蓝宝石 | 2 | 6.7% |
| 碧蓝 | 1 | 3.3% |
| 紫 | 1 | 3.3% |
| 靛青 | 1 | 3.3% |
| 钴蓝 | 1 | 3.3% |
| 蓝 | 1 | 3.3% |
+ 2 more answers
Random letter · English
n = 30 · H = 3.10 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| m | 7 | 23.3% |
| k | 7 | 23.3% |
| j | 4 | 13.3% |
| q | 3 | 10.0% |
| v | 2 | 6.7% |
| u | 1 | 3.3% |
| s | 1 | 3.3% |
| g | 1 | 3.3% |
+ 4 more answers
Random number 1-10 · English
n = 29 · H = 0.79 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 86.2% |
| 6 | 2 | 6.9% |
| 5 | 1 | 3.4% |
| 8 | 1 | 3.4% |
Random number 1-10 · Chinese
n = 30 · H = 0.88 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 83.3% |
| 4 | 3 | 10.0% |
| 3 | 1 | 3.3% |
| 5 | 1 | 3.3% |
Random number 1-100 · English
n = 30 · H = 3.24 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 7 | 23.3% |
| 47 | 6 | 20.0% |
| 57 | 4 | 13.3% |
| 67 | 3 | 10.0% |
| 75 | 2 | 6.7% |
| 12 | 1 | 3.3% |
| 25 | 1 | 3.3% |
| 27 | 1 | 3.3% |
+ 5 more answers
Random number 1-100 · Chinese
n = 30 · H = 1.61 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 37 | 21 | 70.0% |
| 42 | 3 | 10.0% |
| 57 | 2 | 6.7% |
| 38 | 1 | 3.3% |
| 43 | 1 | 3.3% |
| 53 | 1 | 3.3% |
| 71 | 1 | 3.3% |
Want to verify your API really serves DeepSeek V4 Pro?
Point the free fingerprint checker at your endpoint: it samples the same probe questions from your browser and compares the distributions against this reference. Your API key never leaves your browser.
Verify your endpointData source & license
Distributions: Tomáš Bruckner, "One Token Is Enough" (arXiv:2607.10252), official dataset Zenodo DOI 10.5281/zenodo.21278557, licensed CC-BY-4.0. Collected via OpenRouter at temperature 1.0 under the paper's fixed minimal one-word system prompt; answer keys are re-normalized with the checker's pipeline (color aliases, number words, coin h/t) so live probes are directly comparable.