GPT-4.1 Nano - NC Bench

openai/gpt-4.1-nano

GPT-4.1 Nano

via OpenRouter

Release Date

Apr 14th, 2025

Context Size

Reasoning

Benchmark Cost

$0.25

Speed

202.2 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	75	68	68	67	63	68%
Horror: alone in an eerie place at night Creative Writing Hallucination	79	73	73	69	67	72%
Literary fiction: old friends reunite Creative Writing Hallucination	77	73	71	70	69	72%
Mystery: examining a crime scene Creative Writing Hallucination	75	74	74	71	66	72%
Romance: separated couple reunites Creative Writing Hallucination	74	70	70	67	65	69%
Thriller: chase through city streets Creative Writing Hallucination	82	81	78	77	73	78%
Detailed Writing Rules						72.02%
genre
Fantasy: entering an ancient ruin Creative Writing Hallucination	70	67	66	65	61	66%
Horror: alone in an eerie place at night Creative Writing Hallucination	75	72	71	68	67	71%
Literary fiction: old friends reunite Creative Writing Hallucination	71	70	67	67	64	68%
Mystery: examining a crime scene Creative Writing Hallucination	75	74	74	71	68	72%
Romance: separated couple reunites Creative Writing Hallucination	70	69	66	66	64	67%
Thriller: chase through city streets Creative Writing Hallucination	87	81	76	70	68	76%
genre						69.96%
Novelcrafter Default Prompt
Fantasy: entering an ancient ruin Creative Writing Hallucination	76	74	74	72	61	71%
Horror: alone in an eerie place at night Creative Writing Hallucination	82	74	74	74	67	74%
Literary fiction: old friends reunite Creative Writing Hallucination	82	74	73	72	69	74%
Mystery: examining a crime scene Creative Writing Hallucination	81	77	76	75	74	77%
Romance: separated couple reunites Creative Writing Hallucination	76	76	74	73	68	73%
Thriller: chase through city streets Creative Writing Hallucination	82	81	80	78	74	79%
Novelcrafter Default Prompt						74.79%
72.26%

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	79	76	76	75	72	76%
Medium: The Hollow (Inferred) Tooling Reasoning	83	80	79	79	79	80%
Medium: Through the Thornveil (Scattered) Tooling Reasoning	74	74	71	70	49	68%
Short: The Rusty Lantern (Explicit) Tooling Reasoning	90	81	77	72	69	78%
75.33%

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	100	100	100	100	100	26	93%
Long text (~1594 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	100	100	30	93%
Short text (~524 words), big codex (51 entries) Hallucination	100	100	100	100	25	2	1	1	1	1	43%
Short text (~524 words), small codex (11 entries) Hallucination	100	100	100	100	100	31	29	28	27	26	64%
basic entries											73.16%
detailed entries
Long text (~1594 words), big codex (51 detailed entries) Hallucination	100	100	100	100	26	26	25	3	2	1	48%
Long text (~1594 words), small codex (11 detailed entries) Hallucination	100	100	100	100	100	100	100	50	25	3	78%
Short text (~524 words), big codex (51 detailed entries) Hallucination	100	100	42	27	27	27	26	26	1	1	38%
Short text (~524 words), small codex (11 detailed entries) Hallucination	100	100	100	30	29	28	28	27	27	27	50%
detailed entries											53.33%
63.25%

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	51	35	33	17	17	16	3	3	0	0	18%
Large codex (40 entries), short passage (165 words) Tooling Reasoning	51	22	20	19	17	17	13	3	3	0	17%
Small codex (7 entries), long passage (734 words) Tooling Reasoning	33	33	25	24	23	20	0	0	0	0	16%
Small codex (7 entries), short passage (165 words) Tooling Reasoning	73	70	65	61	53	53	53	37	28	17	51%
matrix											25.25%
tiers
5 codex entries Tooling Reasoning	57	57	57	57	44	33	17	0	0	0	32%
10 codex entries Tooling Reasoning	56	33	17	17	0	0	0	0	0	0	12%
20 codex entries Tooling Reasoning	33	33	24	17	17	17	3	3	0	0	15%
40 codex entries Tooling Reasoning	33	18	17	17	17	17	17	17	0	0	15%
tiers											18.56%
21.91%

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	0	0	0	0	0	0	0	0	0	0	0%
Future event time Reasoning	100	100	100	100	100	100	100	100	100	50	95%
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	100	100%
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	0	0	0	0	0	0	0	0	0	0	0%
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%
82.92%

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	50	50	50	49	48	43	43	34	30	26	42%
Write 200 words with 50% dialogue Rule Following Utility	50	50	50	49	48	48	45	43	30	0	41%
Write 200 words with 90% dialogue Rule Following Utility	100	99	96	92	63	58	41	22	18	2	59%
dialogue-200											47.62%
dialogue-500
Write 500 words with 30% dialogue Rule Following Utility	0	0	0	0	0	0	0	0	0	0	0%
Write 500 words with 50% dialogue Rule Following Utility	11	0	0	0	0	0	0	0	0	0	1%
Write 500 words with 70% dialogue Rule Following Utility	24	15	14	13	1	1	0	0	0	0	7%
dialogue-500											2.65%
Ungrouped
Write unattributed dialogue Rule Following	100	100	100	100	100	61	61	61	14	1	70%
31.49%

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	0	0	0	0	20%
Friend got new kittens (German) Language	100	100	100	100	100	100%
Friend got new kittens (Tagalog) Language	100	100	100	100	100	100%
65.00%

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	90	73	93%
Character dialogue (German) in a story Language	100	100	100	100	60	92%
Character dialogue (Hindi) in a story Language	100	100	100	100	50	90%
Character dialogue (Italian) in a story Language	100	100	100	100	50	90%
Character dialogue (Spanish) in a story Language	100	100	100	100	100	100%
92.91%

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	100	100	100	100	100	98	97	96	91	89	97%
Write sentences with 10 words each Utility	84	84	83	83	82	77	75	72	66	55	76%
Write sentences with 20 words each Utility	76	76	76	65	64	59	59	57	38	30	60%
77.78%

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	0	0	0	0	0	0	0	0	0	0	0%
outline-count											66.67%
pov-count
Count point of views for Jack and Olivia Utility	100	100	100	50	50	50	50	50	50	50	65%
Count point of views for Jack Harper Utility	0	0	0	0	0	0	0	0	0	0	0%
Count point of views for Olivia Utility	0	0	0	0	0	0	0	0	0	0	0%
pov-count											21.67%
44.17%

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	97	94	92	83	81	81	58	84%
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	98	98	98	97	96	98%
Expand all contractions Text Editing	98	98	98	97	97	97	97	97%
Location rename: market square, outer ring, bridge, northern mines Text Editing	100	100	100	100	100	96	88	98%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	63	51	51	51	51	51	50	52%
Passive voice → active voice Text Editing Hallucination	84	81	78	73	66	64	60	72%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	100	100	97	96	95	98%
Tense rewriting: past to present Text Editing	97	96	96	93	91	89	86	93%
Generic Prompt								87.96%
Specific Prompt
Avoid said/asked/replied/answered Text Editing	89	78	78	67	67	67	67	73%
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	96	93	86	86	85	85	85	88%
Expand all contractions Text Editing	99	99	99	99	98	98	98	99%
Location rename: market square, outer ring, bridge, northern mines Text Editing	96	96	96	96	96	96	96	96%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	100	100	100	100	95	95	74	95%
Passive voice → active voice Text Editing Hallucination	84	80	76	76	75	72	72	76%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	100	100	100	100	97	100%
Tense rewriting: past to present Text Editing	93	93	89	89	89	86	83	89%
Specific Prompt								90.62%
89.29%

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	67	33	90%
90.00%

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	0	0	0	0	0	0	0	0	0	0	0%
Simple (1-shot) 1-shot Rule Following	100	100	100	100	100	100	100	100	100	100	100%
Simple (5-shot) Few-shot Rule Following	100	100	100	100	100	100	100	100	100	100	100%
Unattributed dialogue Rule Following	0	0	0	0	0	0	0	0	0	0	0%
40.00%

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	100	100	100	100%
20 sentence summary Utility	100	77	54	54	9	9	2	0	0	0	30%
50 sentence summary Utility	100	100	100	77	77	0	0	0	0	0	45%
sentences											75.17%
words
10 word summary Utility	100	100	100	100	100	100	100	100	100	98	100%
20 word summary Utility	100	100	100	100	100	100	100	100	100	98	100%
50 word summary Utility	100	100	100	98	98	98	92	92	92	54	93%
100 word summary Utility	100	100	98	92	77	77	54	54	2	0	65%
200 word summary Utility	100	98	77	27	27	27	0	0	0	0	36%
words											78.66%
82.24%