GPT-5.4 Nano - NC Bench

openai/gpt-5.4-nano

GPT-5.4 Nano

via OpenRouter

Release Date

Mar 17th, 2026

Context Size

400k

Reasoning

Benchmark Cost

$0.99

Speed

122.8 tok/s

Subcategories

Bad Writing Habits

Detects common prose quality anti-patterns in AI-generated creative writing, including passive voice, past progressive overuse, weak dialogue tags, filter words, purple prose, cliches, AI-ism words/adverbs/names, and more.

Scenario	#1	#2	#3	#4	#5	Total
Detailed Writing Rules
Fantasy: entering an ancient ruin Creative Writing Hallucination	78	78	76	76	75	77%
Horror: alone in an eerie place at night Creative Writing Hallucination	86	84	84	83	82	84%
Literary fiction: old friends reunite Creative Writing Hallucination	87	85	84	83	82	84%
Mystery: examining a crime scene Creative Writing Hallucination	85	84	83	83	82	83%
Romance: separated couple reunites Creative Writing Hallucination	85	84	83	82	82	83%
Thriller: chase through city streets Creative Writing Hallucination	87	87	84	82	81	84%
Detailed Writing Rules						82.57%
genre
Fantasy: entering an ancient ruin Creative Writing Hallucination	79	78	78	76	74	77%
Horror: alone in an eerie place at night Creative Writing Hallucination	81	78	77	77	76	78%
Literary fiction: old friends reunite Creative Writing Hallucination	81	76	76	75	71	76%
Mystery: examining a crime scene Creative Writing Hallucination	83	83	82	79	75	80%
Romance: separated couple reunites Creative Writing Hallucination	79	78	78	77	76	78%
Thriller: chase through city streets Creative Writing Hallucination	84	79	77	76	72	78%
genre						77.70%
Novelcrafter Default Prompt
Fantasy: entering an ancient ruin Creative Writing Hallucination	82	80	77	76	75	78%
Horror: alone in an eerie place at night Creative Writing Hallucination	86	86	85	83	82	84%
Literary fiction: old friends reunite Creative Writing Hallucination	82	81	80	77	77	80%
Mystery: examining a crime scene Creative Writing Hallucination	85	84	82	81	81	82%
Romance: separated couple reunites Creative Writing Hallucination	85	81	80	79	79	81%
Thriller: chase through city streets Creative Writing Hallucination	81	80	78	76	76	78%
Novelcrafter Default Prompt						80.55%
80.27%

Codex Extraction

Evaluates a model's ability to extract structured codex entries (characters, locations, objects, lore) from prose passages and return them as well-formed XML.

Scenario	#1	#2	#3	#4	#5	Total
Long: The Spire of Echoes (Dense) Tooling Reasoning	90	89	88	87	76	86%
Medium: The Hollow (Inferred) Tooling Reasoning	89	89	89	88	87	89%
Medium: Through the Thornveil (Scattered) Tooling Reasoning	82	81	77	72	64	75%
Short: The Rusty Lantern (Explicit) Tooling Reasoning	88	87	81	79	78	83%
83.16%

Codex Red Herring (False Positive Detection)

Tests whether models correctly report "no violations" when a codex is fully consistent with the prose passage. Models that hallucinate false violations (false positives) fail. Uses a 2×2 matrix of text length × codex size, with bare and detailed-entry variants.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
basic entries
Long text (~1594 words), big codex (51 entries) Hallucination	100	100	100	100	50	27	17	17	10	2	52%
Long text (~1594 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	31	17	8	7	66%
Short text (~524 words), big codex (51 entries) Hallucination	100	100	100	100	100	100	50	31	28	25	73%
Short text (~524 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	50	25	25	80%
basic entries											67.98%
detailed entries
Long text (~1594 words), big codex (51 detailed entries) Hallucination	100	100	100	100	100	100	100	25	25	25	78%
Long text (~1594 words), small codex (11 detailed entries) Hallucination	100	50	50	35	29	25	25	25	17	6	36%
Short text (~524 words), big codex (51 detailed entries) Hallucination	100	100	100	100	100	100	42	38	38	28	74%
Short text (~524 words), small codex (11 detailed entries) Hallucination	100	100	100	100	100	100	100	50	50	29	83%
detailed entries											67.74%
67.86%

Codex Violation Detection

Detects factual inconsistencies between a story bible and prose passages. The model must output structured XML identifying each violation with paragraph number and substring.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
matrix
Large codex (40 entries), long passage (1,019 words) Tooling Reasoning	41	36	34	30	26	3	0	0	0	0	17%
Large codex (40 entries), short passage (165 words) Tooling Reasoning	79	74	56	53	43	3	0	0	0	0	31%
Small codex (7 entries), long passage (734 words) Tooling Reasoning	63	57	54	53	53	52	33	0	0	0	37%
Small codex (7 entries), short passage (165 words) Tooling Reasoning	97	93	90	88	88	80	79	67	0	0	68%
matrix											38.16%
tiers
5 codex entries Tooling Reasoning	76	76	75	69	67	60	43	0	0	0	47%
10 codex entries Tooling Reasoning	66	53	49	27	3	0	0	0	0	0	20%
20 codex entries Tooling Reasoning	81	73	73	70	51	0	0	0	0	0	35%
40 codex entries Tooling Reasoning	83	80	66	54	54	48	3	0	0	0	39%
tiers											35.04%
36.60%

Data extraction

Extract key details from a given block of text.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
All valid emails Utility	100	100	100	100	100	100	100	100	100	100	100%
Contextual pronoun Utility	100	100	100	100	100	100	100	100	100	100	100%
Fruits excluding citrus Utility	100	100	100	100	100	100	100	100	100	100	100%
Future event time Reasoning	100	100	100	50	50	50	50	50	50	50	65%
Guess the pet Reasoning	100	100	100	100	100	100	100	100	100	100	100%
Highest-rated movie Reasoning	100	100	100	100	100	100	100	100	100	100	100%
Indirect birth year Reasoning	100	100	100	100	100	100	100	100	100	100	100%
What instrument does Lucy play? Reasoning	100	100	100	100	100	100	100	100	100	0	90%
What's the color of the car? Utility	100	100	100	100	100	100	100	100	100	100	100%
What's the correct time? Reasoning	100	100	100	100	100	100	0	0	0	0	60%
Who's the sister? Reasoning	100	100	100	100	100	100	100	100	100	100	100%
Who's the tallest? Reasoning	100	100	100	100	100	100	100	100	100	100	100%
92.92%

Dialogue tags

Various tasks related to dialogue tags in text.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
dialogue-200
Write 200 words with 10% dialogue Rule Following Utility	59	50	47	4	0	0	0	0	0	0	16%
Write 200 words with 50% dialogue Rule Following Utility	50	49	47	44	34	30	6	2	0	0	26%
Write 200 words with 90% dialogue Rule Following Utility	68	59	50	47	25	23	18	18	4	0	31%
dialogue-200											24.56%
dialogue-500
Write 500 words with 30% dialogue Rule Following Utility	25	3	2	1	0	0	0	0	0	0	3%
Write 500 words with 50% dialogue Rule Following Utility	50	36	19	14	0	0	0	0	0	0	12%
Write 500 words with 70% dialogue Rule Following Utility	49	36	33	16	8	3	0	0	0	0	15%
dialogue-500											9.90%
Ungrouped
Write unattributed dialogue Rule Following	100	14	14	1	1	0	0	0	0	0	13%
16.62%

Language Comprehension

Does the model understand more than just English?

Scenario	#1	#2	#3	#4	#5	Total
Asking for directions (Dutch) Language	100	100	0	0	0	40%
Asking for directions (German) Language	100	100	0	0	0	40%
Friend got new kittens (German) Language	100	100	100	100	100	100%
Friend got new kittens (Tagalog) Language	100	100	100	100	100	100%
70.00%

Language Writing

Can the model generate text in different languages?

Scenario	#1	#2	#3	#4	#5	Total
Character dialogue (French) in a story Language	100	100	100	100	100	100%
Character dialogue (German) in a story Language	100	100	100	98	98	99%
Character dialogue (Hindi) in a story Language	100	100	98	55	50	81%
Character dialogue (Italian) in a story Language	100	100	100	97	0	79%
Character dialogue (Spanish) in a story Language	100	100	99	98	97	99%
91.64%

N-Length Sentences

Write sentences with exactly N words

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
Write sentences with 5 words each Utility	89	87	85	78	78	78	78	75	72	70	79%
Write sentences with 10 words each Utility	97	95	92	92	90	87	84	84	81	71	87%
Write sentences with 20 words each Utility	47	11	4	4	4	3	3	1	0	0	8%
58.00%

Novel outline

Handle questions about the outline of a novel in various formats

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
outline-count
Count acts Utility	100	100	100	100	100	100	100	100	100	100	100%
Count chapters Utility	100	100	100	100	100	100	100	100	100	100	100%
Count scenes Utility	100	100	100	0	0	0	0	0	0	0	30%
outline-count											76.67%
pov-count
Count point of views for Jack and Olivia Utility	100	100	100	50	50	50	0	0	0	0	45%
Count point of views for Jack Harper Utility	100	100	100	0	0	0	0	0	0	0	30%
Count point of views for Olivia Utility	100	100	100	0	0	0	0	0	0	0	30%
pov-count											35.00%
55.83%

Text Replacement

Tests deterministic text transformations: renaming characters/locations, expanding contractions, tense rewriting, POV shifts, gender swaps, combined transformations, and word avoidance. Scored by checking each expected change independently.

Scenario	#1	#2	#3	#4	#5	#6	#7	Total
Generic Prompt
Avoid said/asked/replied/answered Text Editing	89	89	78	78	78	67	67	78%
Character rename: Elena->Mirabel, Gregor->Aldric Text Editing	100	100	100	100	100	100	100	100%
Combined: 3rd person past → 1st person present Text Editing	99	99	99	99	99	99	98	99%
Expand all contractions Text Editing	98	98	98	98	98	96	96	98%
Location rename: market square, outer ring, bridge, northern mines Text Editing	100	100	96	96	96	96	96	97%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	99	99	99	93	83	80	75	90%
Passive voice → active voice Text Editing Hallucination	75	74	74	72	71	71	69	72%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	100	100	100	100	99	100%
Tense rewriting: past to present Text Editing	91	91	91	88	88	88	88	90%
Generic Prompt								91.41%
Specific Prompt
Avoid said/asked/replied/answered Text Editing	89	89	89	78	78	67	67	79%
Character rename: Elena->Mirabel, Gregor->Aldric Text Editing	100	100	100	100	100	100	100	100%
Combined: 3rd person past → 1st person present Text Editing	99	98	96	95	94	93	92	95%
Expand all contractions Text Editing	98	97	96	96	95	95	91	95%
Location rename: market square, outer ring, bridge, northern mines Text Editing	100	100	100	100	100	100	100	100%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	100	100	100	100	100	100	99	100%
Passive voice → active voice Text Editing Hallucination	88	82	81	79	78	77	77	80%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	99	99	99	99	98	99%
Tense rewriting: past to present Text Editing	100	99	97	95	92	89	89	94%
Specific Prompt								93.74%
92.57%

Tool usage within Novelcrafter

Output messages that are related to tool usage within Novelcrafter

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
Create alternate prose sections Tooling	100	100	100	100	100	100	100	100	100	100	100%
100.00%

Voice/dialogue sheets

Extract dialogue from given text as voice sheets.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
Multiple speakers Rule Following	0	0	0	0	0	0	0	0	0	0	0%
Simple Rule Following	100	0	0	0	0	0	0	0	0	0	10%
Simple (1-shot) 1-shot Rule Following	100	0	0	0	0	0	0	0	0	0	10%
Simple (5-shot) Few-shot Rule Following	100	100	100	100	100	100	100	100	100	100	100%
Unattributed dialogue Rule Following	100	100	100	0	0	0	0	0	0	0	30%
30.00%

Write N of X

Write exactly N words/sentences/paragraphs...

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
paragraphs
1 paragraph summary Utility	100	100	100	100	100	100	100	100	100	100	100%
3 paragraph summary Utility	100	100	100	100	100	100	100	100	100	100	100%
5 paragraph summary Utility	100	100	100	100	100	100	100	100	100	100	100%
paragraphs											100.00%
sentences
1 sentence summary Utility	100	100	100	100	100	100	100	100	100	100	100%
3 sentence summary Utility	100	100	100	100	100	100	100	100	100	100	100%
10 sentence summary Utility	100	100	100	100	100	100	100	98	98	98	100%
20 sentence summary Utility	100	100	100	100	100	100	98	98	98	92	99%
50 sentence summary Utility	100	100	100	100	100	98	92	0	0	0	69%
sentences											93.46%
words
10 word summary Utility	100	100	100	100	100	100	100	100	100	100	100%
20 word summary Utility	100	100	100	100	100	100	100	100	98	92	99%
50 word summary Utility	100	100	100	98	98	92	77	77	77	54	87%
100 word summary Utility	100	100	92	77	77	54	27	27	27	9	59%
200 word summary Utility	100	0	0	0	0	0	0	0	0	0	10%
words											71.12%
86.37%