AI Desk · Model Identity · Evidence object
Tokenizer signature tk_d1411c9d
An exact tokenizer signature: every model listed below returned the same marginal prompt-token count on all 50 test strings. Sharing a signature is strong evidence of a shared vocabulary. This signature sits in the GPT group.
- Members
- 10
- First observed
- 21 August 2026
- Last observed
- 21 August 2026
- Group
- GPT
Models with this signature
OpenAI: GPT-4.1 Nanoopenai/gpt-4.1-nanoOpenAIOpenAI: GPT-4o-miniopenai/gpt-4o-miniOpenAIOpenAI: GPT-4o-mini (2024-07-18)openai/gpt-4o-mini-2024-07-18OpenAIOpenAI: GPT-5 Nanoopenai/gpt-5-nanoOpenAIOpenAI: GPT-5.1-Codex-Miniopenai/gpt-5.1-codex-miniOpenAIOpenAI: GPT-5.4 Nanoopenai/gpt-5.4-nanoOpenAIOpenAI: GPT-5.6 Lunaopenai/gpt-5.6-lunaOpenAIOpenAI: gpt-oss-120bopenai/gpt-oss-120bOpenAIOpenAI: gpt-oss-20bopenai/gpt-oss-20bOpenAIOpenAI: gpt-oss-safeguard-20bopenai/gpt-oss-safeguard-20bOpenAI
The measured vector
Marginal prompt-token cost per string, as measured on OpenAI: GPT-4.1 NanoAll 50 rows
English and whitespace
en-prose14
en-long17
spaces-203
spaces-603
tabs-203
newlines-204
mixed-ws6
Digits
digits-93
digits-124
digits-3010
digits-sep7
float-long9
CJK
zh-common12
zh-long17
zh-rare20
ja-kana10
ja-kanji13
ko11
Other scripts
ru11
ar11
he10
hi11
th11
el14
Emoji
emoji-basic8
emoji-skin13
emoji-zwj-family11
emoji-zwj-x333
emoji-flags16
emoji-prof20
Rare Unicode
math31
boxdraw27
combining11
cjk-ext-b13
surrogates40
zalgo35
rtl-mix5
Code
py-code25
py-indent15
json20
html16
regex44
camel6
snake6
Repetition and encodings
rare-word-x531
repeat-tok22
base6434
hex11
url17
uuid27
Method: tokenizer fingerprinting, v1-50. Raw data: fingerprints.json · index.json · test-strings.json.