AI model comparison

Mercury 2.5 vs Granite 4.2 8B

Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.

inception logo

Inception

Mercury 2.5

Mercury 2.5 is the fastest reasoning LLM, and the latest diffusion LLM (dLLM) from Inception.

Input / 1M
$0.04
Output / 1M
$0.15
Context
260K

Granite 4.2 8B is a dense reasoning model from IBM. It is suited for mathematics, code generation, multilingual dialogue, and agentic workflows that need multi-step reasoning.

Input / 1M
$0.06
Output / 1M
$0.25
Context
131K

At a glance

Quick verdict

How the two models stack up on the things people ask about most.

Lower price

inception logo

Mercury 2.5

1.6x cheaper for a typical chat

Higher intelligence score

inception logo

Mercury 2.5

12.3 vs 11.1 on Artificial Analysis

Larger context window

inception logo

Mercury 2.5

260K vs 131K tokens

Newer release

inception logo

Mercury 2.5

Released September 8, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

inception logoMercury 2.512.3
ibm-granite logoGranite 4.2 8B11.1

Coding index

inception logoMercury 2.5Not available
ibm-granite logoGranite 4.2 8B22.4

Agentic index

inception logoMercury 2.5Not available
ibm-granite logoGranite 4.2 8B1.3

Pricing

Mercury 2.5 vs Granite 4.2 8B API pricing

Per-token API rates. Cheaper option highlighted.

Metricinception logoMercury 2.5ibm-granite logoGranite 4.2 8B
Input tokensPer 1M tokens$0.04$0.06
Output tokensPer 1M tokens$0.15$0.25
Cached input (read)Per 1M tokens$0.00$0.02
Cache writePer 1M tokensNot availableNot available

What it costs in practice

Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.

Chat message

2K in, 500 out

inception logoMercury 2.5$0.16
ibm-granite logoGranite 4.2 8B$0.25

Coding task

30K in, 4K out

inception logoMercury 2.5$1.80$0.72 cached
ibm-granite logoGranite 4.2 8B$2.80$1.45 cached

Long document summary

150K in, 2K out

inception logoMercury 2.5$6.30$0.90 cached
ibm-granite logoGranite 4.2 8B$9.50$2.75 cached

Specs

Context window and capabilities

How much each model can read, how much it can write, and what it accepts as input.

Metricinception logoMercury 2.5ibm-granite logoGranite 4.2 8B
Context window260K tokens131K tokens
Max output66K tokens118K tokens
Input typesTextText
Output typesTextText
Reasoning effort levelsHigh, Medium, Low, NoneHigh, Low, None
Default reasoning effortMediumHigh
Release dateSeptember 8, 2026August 31, 2026

Features

Supported features

API features available for each model.

Metricinception logoMercury 2.5ibm-granite logoGranite 4.2 8B
Tool callingSupportedSupported
Structured outputsSupportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureSupportedSupported
Stop sequencesSupportedSupported
Deterministic seedNot supportedSupported
Verbosity controlNot supportedNot supported

Our take

Mercury 2.5 is 1.6x cheaper for a typical chat. Mercury 2.5 scores higher on the Artificial Analysis Intelligence Index (12.3 vs 11.1). Mercury 2.5 has the larger context window (260K vs 131K tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.

FAQ

Frequently asked questions

Is Mercury 2.5 or Granite 4.2 8B cheaper?

Mercury 2.5 is cheaper for a typical chat (2K input tokens and 500 output tokens). Mercury 2.5 costs $0.04 per 1M input tokens and $0.15 per 1M output tokens, while Granite 4.2 8B costs $0.06 per 1M input tokens and $0.25 per 1M output tokens.

Which has a bigger context window, Mercury 2.5 or Granite 4.2 8B?

Mercury 2.5 supports up to 260K tokens of context, compared with 131K for Granite 4.2 8B.

Is Mercury 2.5 smarter than Granite 4.2 8B?

On the Artificial Analysis Intelligence Index, Mercury 2.5 scores 12.3 and Granite 4.2 8B scores 11.1, putting Mercury 2.5 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.

Can I use Mercury 2.5 and Granite 4.2 8B at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Mercury 2.5 and Granite 4.2 8B answer side by side and keep the better response.

inception logoibm-granite logo

Why choose? Ask both.

Send one prompt to Mercury 2.5 and Granite 4.2 8B at the same time. Compare the answers side by side and keep the best one.