AI Models · Paid vs Paid

o3 Paid vs INMercury 2.5 Paid

o3 vs Mercury 2.5 compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.

Prices & specs refreshed from live data · olud.ai

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

o3PaidOpenAI
$2 /M input
$8 /M outputManaged API (no infra to run)
TypeProprietary
Context window200K 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 $8/M). It also gives you the larger 260K context window.

o3 vs Mercury 2.5 specs

Speco3Mercury 2.5Winner
MakerOpenAIInception
TypeProprietaryProprietary
Context window200K tokens260K tokensINMercury 2.5
Input price$2/M$0.04/MINMercury 2.5
Output price$8/M$0.15/MINMercury 2.5
Vision / multimodalYesNoo3
Tool / function callingYesYes= Tie
Self-hostableNo (API only)No (API only)
LicenseProprietaryProprietary

Price gap & when to choose each

53×cheaper per output token

Mercury 2.5 is ~53× cheaper than o3 on output tokens ($0.15 vs $8 per M tokens).

Choose o3 if…
  • You want frontier performance through a managed API
  • 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 need the longer 260K context window
  • You want the lower output price
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

Capabilityo3Mercury 2.5
Open weights (downloadable)
Self-hostable
Runs fully offline
Vision / multimodal
Tool / function calling
1M+ context window

Benchmarks: o3 vs Mercury 2.5

Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).

o3
Mercury 2.5
Intelligence index
20.2
Math index
88.3
GPQA
82.7%
MMLU-Pro
85.3%
Humanity's Last Exam
20.1%
Long Context Reasoning
74.7%
LiveCodeBench
80.8%
MATH-500
99.2%
AIME
90.3%
AIME 2025
88.3%
IFBench
71.4%
τ²-Bench
80.7%
Terminal-Bench Hard
37.1%
Speed
114.5 tok/s
Latency
6.58s
Intelligence per $
5.8

Benchmark data by Artificial Analysis.

How o3 and Mercury 2.5 score

🤝 Neck and neck on these criteria (3.0 vs 3.0 / 5).
Criteriono3Mercury 2.5
Cost-efficiency3.55.0
Context window4.04.0
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

o3 Paid

OpenAI · Proprietary

o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks. It also excels at technical writing and instruction-following....

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...

Other models in these families

These variants are tracked but not compared here — one page per family keeps the comparison readable.

Other variants tracked
o3 Proo3 (batch)o3 Minio3 Mini (batch)o3 Mini High

Frequently asked questions

o3 vs Mercury 2.5 — which is cheaper?

Mercury 2.5 is cheaper on output ($0.15/M vs $8/M).

Which has the larger context window?

Mercury 2.5 offers the larger context window (260K tokens).

o3 vs Mercury 2.5 — which should I pick in 2026?

Choose Mercury 2.5 for the lower output price ($0.15/M vs $8/M). It also gives you the larger 260K context window.

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