AI model comparison

Claude Sonnet 5.5 vs Muse Spark 1.3

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

Claude Sonnet 5.5 is Anthropic's Sonnet-class model for well-scoped everyday work, succeeding Claude Sonnet 5 as a direct upgrade.

Input / 1M
$2
Output / 1M
$10
Context
1M

Muse Spark 1.3 is a multimodal reasoning model from Meta for long-running agentic, multi-agent, and coding workflows.

Input / 1M
$1.25
Output / 1M
$4.25
Context
1.05M

At a glance

Quick verdict

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

Lower price

meta logo

Muse Spark 1.3

1.9x cheaper for a typical chat

Higher intelligence score

anthropic logo

Claude Sonnet 5.5

56 vs 48.1 on Artificial Analysis

Larger context window

meta logo

Muse Spark 1.3

1.05M vs 1M tokens

Newer release

anthropic logo

Claude Sonnet 5.5

Released September 28, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

anthropic logoClaude Sonnet 5.556
meta logoMuse Spark 1.348.1

Coding index

anthropic logoClaude Sonnet 5.5Not available
meta logoMuse Spark 1.375.8

Agentic index

anthropic logoClaude Sonnet 5.5Not available
meta logoMuse Spark 1.355.5

Pricing

Claude Sonnet 5.5 vs Muse Spark 1.3 API pricing

Per-token API rates. Cheaper option highlighted.

Metricanthropic logoClaude Sonnet 5.5meta logoMuse Spark 1.3
Input tokensPer 1M tokens$2$1.25
Output tokensPer 1M tokens$10$4.25
Cached input (read)Per 1M tokens$0.10$0.15
Cache writePer 1M tokens$2.50Not available
Web searchPer request$0.01$0.0025

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

anthropic logoClaude Sonnet 5.5$9
meta logoMuse Spark 1.3$4.63

Coding task

30K in, 4K out

anthropic logoClaude Sonnet 5.5$100$43 cached
meta logoMuse Spark 1.3$54.50$21.50 cached

Long document summary

150K in, 2K out

anthropic logoClaude Sonnet 5.5$320$35 cached
meta logoMuse Spark 1.3$196$31 cached

Specs

Context window and capabilities

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

Metricanthropic logoClaude Sonnet 5.5meta logoMuse Spark 1.3
Context window1M tokens1.05M tokens
Max output128K tokens944K tokens
Input typesFile, Image, TextFile, Image, Text, Video
Output typesTextText
Reasoning effort levelsMax, Extra high, High, Medium, LowMax, Extra high, High, Medium, Low, Minimal
Default reasoning effortHighMedium
Release dateSeptember 28, 2026September 2, 2026

Features

Supported features

API features available for each model.

Metricanthropic logoClaude Sonnet 5.5meta logoMuse Spark 1.3
Tool callingSupportedSupported
Structured outputsSupportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureNot supportedSupported
Stop sequencesSupportedNot supported
Deterministic seedNot supportedNot supported
Verbosity controlSupportedNot supported

Our take

Muse Spark 1.3 is 1.9x cheaper for a typical chat. Claude Sonnet 5.5 scores higher on the Artificial Analysis Intelligence Index (56 vs 48.1). Muse Spark 1.3 has the larger context window (1.05M vs 1M 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 Claude Sonnet 5.5 or Muse Spark 1.3 cheaper?

Muse Spark 1.3 is cheaper for a typical chat (2K input tokens and 500 output tokens). Muse Spark 1.3 costs $1.25 per 1M input tokens and $4.25 per 1M output tokens, while Claude Sonnet 5.5 costs $2 per 1M input tokens and $10 per 1M output tokens.

Which has a bigger context window, Claude Sonnet 5.5 or Muse Spark 1.3?

Muse Spark 1.3 supports up to 1.05M tokens of context, compared with 1M for Claude Sonnet 5.5.

Is Claude Sonnet 5.5 smarter than Muse Spark 1.3?

On the Artificial Analysis Intelligence Index, Claude Sonnet 5.5 scores 56 and Muse Spark 1.3 scores 48.1, putting Claude Sonnet 5.5 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.

Can I use Claude Sonnet 5.5 and Muse Spark 1.3 at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Claude Sonnet 5.5 and Muse Spark 1.3 answer side by side and keep the better response.

anthropic logometa logo

Why choose? Ask both.

Send one prompt to Claude Sonnet 5.5 and Muse Spark 1.3 at the same time. Compare the answers side by side and keep the best one.