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Claude Opus 5 vs Fugu Ultra v2

Published LiveBench scores across all seven categories, live list pricing, context windows, and the measured cost of a point of capability — for both models, side by side.

OpenRouter + LiveBenchAll comparisonsFull leaderboard

Claude Opus 5 is the cheaper of the two; neither can be ranked on quality here.

Fugu Ultra v2 does not have a published LiveBench run, so this comparison covers price, context and declared capabilities only. A missing score means "not evaluated", not "worse" — the right way to separate these two is an eval on your own workload.

anthropic

Claude Opus 5

Blended / 1M
$10.00
Context
1M
Released
Jul 24, 2026
Overall score
80.1
reasoningtool callingimage inputfile inputprompt caching

sakana

Fugu Ultra v2

Blended / 1M
$11.25
Context
1M
Released
Sep 11, 2026
Overall score
Not evaluated
reasoningtool callingimage inputfile inputprompt caching

Specs and pricing

MetricClaude Opus 5Fugu Ultra v2
LiveBench overall

Mean of the seven LiveBench category scores, 0–100. Higher is better.

80.1
Cost per point

Measured benchmark spend divided by overall score — dollars per point of capability.

$0.3950
Blended price / 1M

3:1 input:output mix, the usual shape of production traffic.

$10.00win$11.25
Input price / 1M$5.00$5.00
Output price / 1M$25.00win$30.00
Cached input / 1M

Price of an input token served from the prompt cache, where the provider publishes one.

$0.500$0.500
Context window1M1M
Max output tokens128K128K

Benchmarks by category

An overall score averages away the thing you probably care about. These are the seven LiveBench categories scored separately — Claude Opus 5 on top, Fugu Ultra v2 below, both out of 100.

Agentic coding
65.2
Coding
81.4
Reasoning
91.2
Mathematics
95.7
Data analysis
74.6
Language
88.7
Instruction following
63.8

What each one costs to run

Per-token prices are hard to feel. These are monthly list costs for both models across five workload shapes, using each provider's published cached-input rate where there is one.

WorkloadClaude Opus 5Fugu Ultra v2
Support chatbot

1.2K in / 400 out × 200K requests

$2,876/mo$3,276/mo
RAG assistant

8K in / 600 out × 100K requests

$3,700/mo$4,000/mo
Coding agent

40K in / 4K out × 20K requests

$3,480/mo$3,880/mo
Document extraction

20K in / 1.5K out × 50K requests

$6,650/mo$7,025/mo
Bulk classification

500 in / 20 out × 5M requests

$12,750/mo$13,250/mo
Run these two through the cost calculator

Which should you pick?

You are cost-constrained

Claude Opus 5

Cheaper on blended list price at $10.00 per million tokens.

Claude Opus 5 vs Fugu Ultra v2 FAQ

Which is better, Claude Opus 5 or Fugu Ultra v2?

Claude Opus 5 is the cheaper of the two; neither can be ranked on quality here. Fugu Ultra v2 does not have a published LiveBench run, so this comparison covers price, context and declared capabilities only. A missing score means "not evaluated", not "worse" — the right way to separate these two is an eval on your own workload.

Is Claude Opus 5 cheaper than Fugu Ultra v2?

Claude Opus 5 is cheaper. On a 3:1 input:output blend, Claude Opus 5 lists at $10.00 per million tokens and Fugu Ultra v2 at $11.25 — Claude Opus 5 is 13% cheaper. Input and output are priced separately — Claude Opus 5 charges $5.00 in and $25.00 out, Fugu Ultra v2 charges $5.00 and $30.00 — so the model that looks cheaper flips depending on how output-heavy your workload is.

Does Claude Opus 5 or Fugu Ultra v2 have a bigger context window?

They are effectively the same — 1M for Claude Opus 5 and 1M for Fugu Ultra v2.

Do Claude Opus 5 and Fugu Ultra v2 support prompt caching?

Both publish a cached-input rate: $0.500 per million for Claude Opus 5 and $0.500 for Fugu Ultra v2, against full input rates of $5.00 and $5.00. On a workload with a long stable prefix — a system prompt, a tool schema, a retrieved corpus — that changes the economics more than the headline price does.

Related comparisons

How these numbers are produced

  • Price — provider list price from OpenRouter, refreshed every 15 minutes. “Blended” is a 3:1 input:output mix.
  • ScoresLiveBench release 2026-06-25, using their own category map. Each model shows its strongest published run. A blank means “not evaluated”, never “bad”.
  • Cost per point — the measured dollars LiveBench spent on the run, divided by the score it earned.
  • “Win” — awarded only past a threshold: one full point on a benchmark score, 10% on a price, 25% on a context window. Anything tighter reports as a tie, because effort settings alone move a LiveBench score by more than that.

Published benchmarks rank models on someone else's tasks. Before committing, see LLM & agent evaluation for building an eval on your own.