AI leaderboard · Hard prompts

Best AI for hard prompts: 417 models ranked by blind votes

Prompts the arena’s classifier rates as hard: specific, technical and needing several steps to solve. Ranked by LMArena’s blind votes, every score with its margin of error and, beside it, the list price of each model on our price list.

Scores from LMArena, published 20 October 2026, under CC BY 4.0. Prices from each maker’s pricing page, read on 15 October 2026.

Top score
1549Gemini 4 Argon (High) from Google
Models ranked
417
Level with the leader
2
On our price list
1
Published
20 October 2026

Level: the votes cannot separate it from the leader.

On LMArena’s Hard prompts board, Gemini 4 Argon (High) from Google leads with 1549 points from 3,131 blind votes, published 20 October 2026. One other model is statistically level with it. None of the models it ranks has an API price on our list yet.

Best AI for hard prompts

Prompts the arena’s classifier rates as hard: specific, technical and needing several steps to solve.

LMArena scores of 51 AI models, with their 95% intervals, votes and list prices
#ModelScoreVotesPer 1M tokens, in / out
1Gemini 4 Argon (High)Google154995% interval 1538 to 15603,131·
1Claude Opus 5.5 (High)Anthropic153495% interval 1525 to 15435,917·
2Claude Opus 4.6 (High)Anthropic153195% interval 1526 to 153552,600·
2Claude Fable 5 (High)Anthropic152995% interval 1524 to 153428,193·
2Claude Opus 4.6Anthropic152795% interval 1523 to 153156,652·
2Claude Opus 4.7 (High)Anthropic152595% interval 1521 to 153043,676·
2Claude Fable 5.1 (Max)Anthropic152395% interval 1516 to 15309,089·
2Muse Wonder (Max)Meta152395% interval 1512 to 15343,187·
5Claude Opus 4.7Anthropic151995% interval 1515 to 152344,373·
5Gemini 3.8 Flash (High)Google151795% interval 1512 to 152326,670·
5Muse Spark 1.3 (Max)Meta151795% interval 1510 to 152312,510·
6Kimi K3 (Max)Moonshot AI · open weights151695% interval 1511 to 152221,953·
6Claude Opus 5 (Max)Anthropic151695% interval 1510 to 152121,745·
7Claude Opus 5 (High)Anthropic151595% interval 1510 to 151945,136·
7Claude Opus 4.8 (High)Anthropic151395% interval 1508 to 151742,516·
7GPT-5.6 Sol (xHigh)OpenAI151195% interval 1506 to 151627,137·
7Muse Spark 1.2 (xHigh)Meta151195% interval 1503 to 15196,116·
8Muse Spark 1.1Meta151095% interval 1505 to 151529,563·
8Claude Sonnet 5.5 (xHigh)Anthropic150695% interval 1497 to 15155,015·
8MiMo-V2.6-ProXiaomi · open weights150495% interval 1492 to 15162,619·
9Gemini 3.7 Flash (High)Google150795% interval 1502 to 151319,036·
9Muse SparkMeta150695% interval 1499 to 15139,159·
11Gemini 3.1 Pro PreviewGoogle150895% interval 1504 to 151184,197·
11GPT-6.1 Sol (Max)OpenAI150295% interval 1493 to 15124,318·
12GLM-5.3 (Max)Z.ai · open weights150495% interval 1498 to 151015,149·

Where the ranking comes from

The scores, intervals and ranks are LMArena’s. The prices are ours.

Blind votes
LMArena puts the same prompt to two anonymous models and asks the person who wrote it to pick the better answer. The votes place every model on one scale, where a gap of 100 points means the higher model wins about 64 times in 100.
Style control
The scores discount answer length and formatting, so a model does not climb by writing more or by adding headings and lists.
Shared ranks
A model’s rank is one plus the number of models whose whole 95% interval sits above its own. Models the votes cannot separate share a rank, which is why several can be first.
Settings
A model can appear more than once, at different reasoning settings: the line under its name gives the entry as LMArena lists it. Entries with web search switched on are a different product and carry no price.
Prices
The list price per million tokens from the maker’s own pricing page, read on 15 October 2026. It is a price per token, not per answer: a higher reasoning setting spends more tokens on the same question.

Source: LMArena, leaderboard dataset (revision 9041150e, published 20 October 2026), licensed under CC BY 4.0. We change no score: we add the prices and the links to our model pages.

What each of them costs to run

The price list works three everyday jobs on every model, and our own benchmark runs them on real business tasks to see which pass.

Scores published 20 October 2026