AI Models · Paid vs Paid

SAFugu Ultra v2 Paid vs INMercury 2.5 Paid

Fugu Ultra v2 vs Mercury 2.5 compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.

Fugu Ultra v2 — full profile ›  ·  Mercury 2.5 — full profile ›

Prices & specs refreshed from live data · olud.ai

Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.

SAFugu Ultra v2PaidSakana AI
$5 /M input
$30 /M outputManaged API (no infra to run)
TypeProprietary
Context window1M tokens
MultimodalYes
Self-hostNo
INMercury 2.5PaidInception
$0.04 /M input
$0.15 /M outputManaged API (no infra to run)
TypeProprietary
Context window260K tokens
MultimodalNo
Self-hostNo
Choose Mercury 2.5 for the lower output price ($0.15/M vs $30/M). Choose Fugu Ultra v2 if you need the larger 1M context window.

Fugu Ultra v2 vs Mercury 2.5 specs

SpecFugu Ultra v2Mercury 2.5Winner
MakerSakana AIInception–
TypeProprietaryProprietary–
Context window1M tokens260K tokensSAFugu Ultra v2
Input price$5/M$0.04/MINMercury 2.5
Output price$30/M$0.15/MINMercury 2.5
Vision / multimodalYesNoSAFugu Ultra v2
Tool / function callingYesYes= Tie
Self-hostableNo (API only)No (API only)–
LicenseProprietaryProprietary–

Price gap & when to choose each

200×cheaper per output token

Mercury 2.5 is ~200× cheaper than Fugu Ultra v2 on output tokens ($0.15 vs $30 per M tokens).

SAChoose Fugu Ultra v2 if…
  • You want frontier performance through a managed API
  • You need the longer 1M context window
  • You value reliability & ecosystem
  • You don't want to manage infrastructure
INChoose Mercury 2.5 if…
  • You want frontier performance through a managed API
  • You want the lower output price
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

CapabilityFugu Ultra v2Mercury 2.5
Open weights (downloadable)✗✗
Self-hostable✗✗
Runs fully offline✗✗
Vision / multimodal✓✗
Tool / function calling✓✓
1M+ context window✓✗

How Fugu Ultra v2 and Mercury 2.5 score

🤝 Neck and neck on these criteria (3.1 vs 3.0 / 5).
CriterionFugu Ultra v2Mercury 2.5
Cost-efficiency3.05.0
Context window5.04.0
Openness1.51.5
Self-hosting1.01.0
Multimodality5.03.5

Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.

What each model is

Fugu Ultra v2 Paid

Sakana AI · Proprietary

Fugu Ultra v2 is the higher-performance model in Sakana AI's Fugu family. Rather than a single monolithic model, Fugu is a learned multi-agent orchestration system: a language model trained to...

Mercury 2.5 Paid

Inception · Proprietary

Mercury 2.5 is the fastest reasoning LLM, and the latest diffusion LLM (dLLM) from Inception. Instead of generating tokens sequentially, Mercury 2.5 produces and refines multiple tokens in parallel, achieving...

Frequently asked questions

Fugu Ultra v2 vs Mercury 2.5 — which is cheaper?

Mercury 2.5 is cheaper on output ($0.15/M vs $30/M).

Which has the larger context window?

Fugu Ultra v2 offers the larger context window (1M tokens).

Fugu Ultra v2 vs Mercury 2.5 — which should I pick in 2026?

Choose Mercury 2.5 for the lower output price ($0.15/M vs $30/M). Choose Fugu Ultra v2 if you need the larger 1M context window.

People also compare

Hy3 vs Fugu Ultra v2Hy3 vs Mercury 2.5GLM 5.3 vs Fugu Ultra v2GLM 5.3 vs Mercury 2.5DeepSeek V4.1 Flash vs Fugu Ultra v2DeepSeek V4.1 Flash vs Mercury 2.5

Explore more open-source AI

Browse the full open-source model leaderboard, thousands of tools and live benchmarks — all in one place.

Open the leaderboard →