Model Comparator

Compare up to four models using the same criteria.

Claude Sonnet 5.5 (Low, Default Fallback)
Anthropic
Grok 4.20 0309 v2 (Reasoning)
SpaceXSI

Differences only

✓ Best published value among measured models. — Data unavailable. These metrics do not establish an overall ranking.

Model Comparator
Metrics	Claude Sonnet 5.5 (Low, Default Fallback) Anthropic	Grok 4.20 0309 v2 (Reasoning) SpaceXSI
Intelligence	25.6	Best: 25.7
Speed	92.7 t/s	Best: 116 t/s
TTFT	Best: 1.27 s	19.3 s
Input · $ / 1M tokens	$2×1.6 relative to the lowest price among the compared models	Best: $1.25
Output · $ / 1M tokens	$10×4 relative to the lowest price among the compared models	Best: $2.50
Context window	1M	Best: 2M
Reasoning	Yes	Yes
Open weights	No	No
Cost / task	$0.511	—

Intelligence

Claude Sonnet 5.5 (Low, Default Fallback): 25.6
Grok 4.20 0309 v2 (Reasoning): Best: 25.7

Speed

Claude Sonnet 5.5 (Low, Default Fallback): 92.7 t/s
Grok 4.20 0309 v2 (Reasoning): Best: 116 t/s

TTFT

Claude Sonnet 5.5 (Low, Default Fallback): Best: 1.27 s
Grok 4.20 0309 v2 (Reasoning): 19.3 s

Input · $ / 1M tokens

Claude Sonnet 5.5 (Low, Default Fallback): $2×1.6 relative to the lowest price among the compared models
Grok 4.20 0309 v2 (Reasoning): Best: $1.25

Output · $ / 1M tokens

Claude Sonnet 5.5 (Low, Default Fallback): $10×4 relative to the lowest price among the compared models
Grok 4.20 0309 v2 (Reasoning): Best: $2.50

Context window

Claude Sonnet 5.5 (Low, Default Fallback): 1M
Grok 4.20 0309 v2 (Reasoning): Best: 2M

Reasoning

Claude Sonnet 5.5 (Low, Default Fallback): Yes
Grok 4.20 0309 v2 (Reasoning): Yes

Open weights

Claude Sonnet 5.5 (Low, Default Fallback): No
Grok 4.20 0309 v2 (Reasoning): No

Cost / task

Claude Sonnet 5.5 (Low, Default Fallback): $0.511
Grok 4.20 0309 v2 (Reasoning): —

Each reasoning level remains a separate configuration.

Score and cost

Each line joins the reasoning levels of a compared model; the large point marks the configuration in the table. The top-right corner holds the best score for the lowest cost. Select another point to compare that level.

Claude Sonnet 5.5 (Low, Default Fallback)25.6 · $4
Grok 4.20 0309 v2 (Reasoning)25.7 · $1.56