BenchLeader

Mercury 2.5

Reasoning effort

Mercury 2.5 is an Inception proprietary reasoning model, released 8 Sept 2026. Its best configuration ranks #520 of 785 on the BenchLeader Index at 45.3 ±7.2, in the lower half. The ± is the point: 409 other configurations score within that range, so they and this one cannot be told apart on quality alone — price and speed are what separate them. It scores highest in long context (61) and lowest in maths (31). At $0.375 per million tokens blended it is cheaper than most ranked models. Output speed of 742 tokens per second puts it in the fastest quarter, with a first answer in 3.8 s. It has been measured at 2 reasoning-effort settings; this summary describes the best-scoring one, and the tabs above switch between them. Last measured 8 Sept 2026.

Blended price
$0.375/M
$0.250 in · $0.750 out
Output speed
742 tok/s
measured by Artificial Analysis
First answer
3.75 s
first token 1.00 s
Context
260k
Full answer
4.43 s
median, reasoning included
Cost per run
$0.117
one full Intelligence Index run
Released
8 Sept 2026
How it scores by categoryDashed line = average model (50). One step of 15 = one standard deviation.
  1. Overall index45
  2. Reasoning41
  3. Coding38
  4. Maths31
  5. Knowledge44
  6. Long context61
  7. Composite43

Versions

Inception has shipped 3 models under this name. Each is ranked on its own results; a newer version often has fewer results so far, which holds its index nearer the average until more arrive.

ModelReleasedIndexRank
NewMercury 3high19 Oct 2026––
Mercury 2.5this page8 Sept 202645.3#520
Mercury 220 Feb 202646.9#468

Reasoning-effort configurations

The same model behaves differently depending on how much it is allowed to think. Each row is one setting, scored only on the benchmarks that were run at that setting. “Not stated” collects results from publishers that did not say which setting they used; for a reasoning model that is usually its thinking mode, but we do not assume it. Pick a setting here or at the top of the page to see its price, speed and category scores.

EffortIndexRankSpeedFirst answerChat reply costCategories
high––742 tok/s3.75 s$0.0003Agents & tools 25 · Coding 16 · Knowledge 57
not statedbest45.3#520742 tok/s3.75 s$0.0003Coding 38 · Composite 43 · Knowledge 44 · Long context 61 · Maths 31 · Reasoning 41

How its index has moved

23 Sept 2026 to 23 Oct 2026
384654

The index is recomputed from scratch every day, so a line moves when a new benchmark result lands, when a publisher revises a score, or when the models it is normalised against change. Early movement usually means the score is still settling.

Benchmark results

See all LLM benchmarks. One column per reasoning effort. Rank is among every configuration of every model on that benchmark. Hover a score for the run it came from.

Reasoning

Benchmarknot statedSourceTrend
Humanity's Last Exam (AA)not in index11.8%#290Artificial Analysis
CritPt0.0%#315Artificial Analysis

Coding

Benchmarkhighnot statedSourceTrend
SciCodeeffort not stated–38.5%#175SciCode
SciCode (AA)not in indexeffort not stated–38.5%#186Artificial Analysis
IOI2.4%#43–Vals AI
Code Migrationnot in index4.5%#71–Vals AI
Vibe Code Bench v1.1not in index3.7%#103–Vals AI
ALE-Benchnot in index301.6#118–Epoch AI Benchmarking Hub
Terminal-Bench 4.0 (AA)not in indexeffort not stated–0.0%#152Artificial Analysis

Agents & tools

Benchmarkhighnot statedSourceTrend
Terminal-Bench 2.1 (Vals)34.5%#68–Vals AI
GDPval-AA v2.1not in indexeffort not stated–0.0%#124Artificial Analysis
CyberBenchnot in index45.5%#38–Vals AI
Finance Agent v2not in index18.9%#74–Vals AI
Harvey's Legal Agent Benchmark v1not in index0.0%#61–Vals AI
Legal Research Benchnot in index4.3%#75–Vals AI
SkillsBenchnot in index18.1%#33–Vals AI
Tax Agent Benchnot in index2.5%#71–Vals AI
Terminal-Bench 4.0 (Vals)not in index0.0%#50–Vals AI
Terminal-Bench Sciencenot in index0.0%#38–Vals AI
AutomationBenchnot in indexeffort not stated–2.4%#179Artificial Analysis
GDP.pdf (AA)not in indexeffort not stated–3.6%#177Artificial Analysis

Maths

Benchmarknot statedSourceTrend
ProofBench3.0%#74Vals AI

Knowledge

Benchmarkhighnot statedSourceTrend
AA-Omniscienceeffort not stated–-39.5#319Artificial Analysis
LegalBench83.1%#60–Vals AI
Excel Modeling Benchmarknot in index8.8%#72–Vals AI
MedCodenot in index31.3%#91–Vals AI
MedScribenot in index55.1%#102–Vals AI
Public Benefits Bench v1.1not in index45.3%#45–Vals AI
AA-Omniscience: accuracynot in indexeffort not stated–22.6%#271Artificial Analysis
AA-Omniscience: non-hallucinationnot in indexeffort not stated–19.7%#284Artificial Analysis

Long context

Benchmarknot statedSourceTrend
AA-LCR71.7%#196Artificial Analysis

Composite

Benchmarknot statedSourceTrend
AA Intelligence Index v4.3.212.3#335Artificial Analysis

Where to run it

Every provider serving this model through OpenRouter, with throughput and first-token latency measured on live traffic over the last 30 minutes and each provider’s own price. Purple marks the best in each column.

ProviderSpeedFirst tokenInput $/MOutput $/MContextQuantisation
Inception236 tok/s1.00 s$0.040$0.150260k–

Price history

The price above, per 1M tokens, every day it changed.

$0.00$0.206$0.413$0.619$0.825Sept 26Oct 26
input outputnow $0.250 in · $0.750 out

What a task costs

Estimates from list price, output speed and time to first answer for the best configuration. “With caching” assumes three-quarters of the input is served from the prompt cache at $0.020 per 1M. Reasoning tokens are not modelled.

WorkloadTokens in / outCostWith cachingTime
Chat reply400 / 300$0.0003$0.00034.2 s
Summarize a 30-page report12,000 / 600$0.0035$0.00144.6 s
Code edit6,000 / 1,500$0.0026$0.00165.8 s
Agentic coding session60,000 / 4,000$0.018$0.00779.1 s
Structured extraction2,000 / 200$0.0007$0.00034.0 s

More from Inception

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See also

Questions people ask

What are Mercury 2.5's benchmark scores?
As of 24 Oct 2026, Mercury 2.5 scores 45.3 ±7.2 on the BenchLeader Index, strongest in long context (61) and weakest in maths (31). That rests on 6 independent benchmark results, and every score on this page links to its publisher.
How does Mercury 2.5 rank?
Mercury 2.5 is #520 of 785 ranked configurations on 24 Oct 2026. 409 other configurations score within its margin, so the exact position matters less than the band. The leader is Claude Opus 5.5 (max effort) at 72.6.
How much does Mercury 2.5 cost per 1M tokens?
As of 24 Oct 2026, Mercury 2.5 costs $0.250 per 1M input tokens and $0.750 per 1M output tokens, $0.375 blended (three input tokens per output token). The list price last changed on 6 Oct 2026.
When was Mercury 2.5 released?
Inception released Mercury 2.5 on 8 Sept 2026. BenchLeader has results for it at 2 reasoning-effort settings.

Data as of 24 Oct 2026. Compare these configurations.

Cite as: BenchLeader, “Mercury 2.5: benchmarks, pricing, speed and rank”, data as of 24 Oct 2026, https://www.benchleader.com/models/mercury-2-5.