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Comparison · 2 models · Updated Oct 4, 2026

Claude Mythos 5 vs Fugu Ultra

Claude Mythos 5 comes out ahead, 36 to 33 on our weighted score, though Fugu Ultra is 44% cheaper per token.

  1. Our pick

    Anthropic

    Claude Mythos 5

    Released Jun 9, 2026

    36/100
    • ECI—
    • Price$10.00 / $50.00
    • Context1M
  2. Sakana AI

    Fugu Ultra

    Released Jun 15, 2026

    33/100
    • ECI—
    • Price$5.00 / $30.00
    • Context1M
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Claude Mythos 5 is our pick

Claude Mythos 5 is the better all-round choice, scoring 36/100 against Fugu Ultra (33). It leads on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceFugu UltraFugu Ultra $11.25 · Claude Mythos 5 $20.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameClaude Mythos 5 1,000,000 · Fugu Ultra 1,000,000 tokens
  • Widest inputsClaude Mythos 5Claude Mythos 5: Text, Images, PDFs · Fugu Ultra: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightClaude Mythos 5Fugu Ultra
Price50%00
Inputs & features30%8070
Context window20%6060
Overall100%36/10033/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Claude Mythos 5 vs Fugu Ultra specifications side by side
SpecificationClaude Mythos 5AnthropicFugu UltraSakana AI
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$10.00$5.00 (best)
Output$50.00$30.00 (best)
Cached input—$0.50
Blended (3:1)$20.00$11.25 (best)
Long-context rateSame rateOver 272K: $10.00 / $45.00
Price sourceMedian of 2 providersOfficial Sakana AI API
Limits
Context window1,000,000 tokens1,000,000 tokens
Max output128,000 tokens—
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYesYeshigh · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model ID—fugu-ultra
API providers211 (best)
ReleasedJun 9, 2026Jun 15, 2026
Knowledge cutoffJan 31, 2026—
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Claude Mythos 5$200.00
  • Fugu Ultra$110.00
04 — Questions

Which should you choose?

Which is better: Claude Mythos 5 or Fugu Ultra?

Claude Mythos 5 is the better all-round choice, scoring 36/100 against Fugu Ultra (33). It leads on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, Claude Mythos 5 or Fugu Ultra?

Fugu Ultra is cheaper at $5.00 input / $30.00 output per million tokens (official Sakana AI API price). Claude Mythos 5 costs $10.00 input / $50.00 output per million tokens (median across 2 API providers). At a typical mix of three input tokens to one output token, that is $11.25 per million tokens for Fugu Ultra versus $20.00 for Claude Mythos 5 (1.8× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. Claude Mythos 5 has not been scored yet and Fugu Ultra has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Claude Mythos 5 and Fugu Ultra yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

Claude Mythos 5 and Fugu Ultra share the same 1,000,000-token context window. Maximum output per response: Claude Mythos 5 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Claude Mythos 5 accepts text, images and PDFs; Fugu Ultra accepts text and images. Claude Mythos 5 handles the widest range of inputs.

Are any of these open source?

No. Claude Mythos 5 and Fugu Ultra are proprietary and only available through APIs and apps.

Which is newer?

Fugu Ultra is the newest, released Jun 15, 2026. Claude Mythos 5 came out Jun 9, 2026. Knowledge cutoff: Claude Mythos 5 Jan 31, 2026.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.