Cost and performance comparison
Claude Sonnet 5 vs Grok 4.5
Model AAnthropic
Claude Sonnet 5
- Cost / 1M Tokens
- $4.40
- 70% in · 30% out mix
- ≈ $6.29 for the same text, tokenizer included
- Value Index (score÷cost)
- 14.6
- Higher = better value
- Speed
- 88/100
- Context
- 1.0M
- Tier
- Smart Tier
List price from the Anthropic pricing page, verified October 12, 2026.
Its tokenizer produces about 43% more tokens than OpenAI's for the same text, so the real cost runs higher than the list price suggests. This is an estimate: the tokenizer has not been measured yet.
Check the sourceModel BxAI
Grok 4.5
- Cost / 1M Tokens
- $3.20
- 70% in · 30% out mix
- Value Index (score÷cost)
- 28.1
- Higher = better value
- Speed
- 89/100
- Context
- 500K
- Tier
- Smart Tier
List price from the xAI pricing page, verified October 12, 2026.
Check the sourceIn-depth analysis
Claude Sonnet 5 vs Grok 4.5: Detailed Comparison
Claude Sonnet 5 is Anthropic's mid-range-tier language model with a 1.0M-token context window, excelling at coding. Grok 4.5 from xAI is a mid-range-tier model supporting 500K tokens in context, with standout performance in reasoning.
This is a genuine tradeoff rather than a clear win. Claude Sonnet 5 leads by 8 points on combined coding and reasoning, and costs 49% more for the same text to do it. The margin is narrow enough that the answer depends on your workload: on tasks where the extra capability shows up, the premium pays for itself; on routine work it does not. Claude Sonnet 5 is priced at $2.00/M input tokens and $10.00/M output tokens. Grok 4.5 costs $2.00/M input and $6.00/M output.
Claude Sonnet 5 turns the same text into about 43% more tokens than Grok 4.5, because their tokenizers differ — so comparing list prices per token understates what Claude Sonnet 5 costs. For the same text, split 70% input and 30% output and counted the way OpenAI's tokenizer counts it, Claude Sonnet 5 works out at about $6.29 per million tokens and Grok 4.5 at $3.20. Every cost figure on this page includes that difference.
On iOPTERA's editorial scores, Claude Sonnet 5 leads with 95/100 for coding and 92/100 for reasoning, against Grok 4.5's 89/100 and 90/100.
Capability breakdown
Across the five core benchmark categories, here is how Claude Sonnet 5 and Grok 4.5 stack up head to head:
Best model by task
- coding: Claude Sonnet 5 wins with 95/100
- reasoning: Claude Sonnet 5 wins with 92/100
- data extraction: Claude Sonnet 5 wins with 92/100
- creative tasks: Claude Sonnet 5 wins with 91/100
- vision/multimodal: Claude Sonnet 5 wins with 90/100
Estimated monthly cost at scale
For 10M + 2M tokens of text a month (counted the way OpenAI's tokenizer counts), Claude Sonnet 5 runs about $57.20 while Grok 4.5 runs about $32.00 — Grok 4.5 saves roughly $25.20 (44%) every month.
What actually decides it
Claude Sonnet 5 and Grok 4.5 come from different labs, which means different tokenizers, different API shapes, and a second vendor relationship. The same English text does not produce the same token count on both, so a price-per-million comparison understates the difference — measure your own prompts on each before treating the headline rates as the full story.
Grok 4.5 and Claude Sonnet 5 were released within 1 months of each other, so they are competing on the same evaluations under roughly the same conditions. That makes a direct benchmark comparison meaningful here in a way it usually is not — neither model has the advantage of being measured on a newer, easier set of tests.
Claude Sonnet 5 carries the larger context window at 1.0M tokens versus 500K for Grok 4.5. The gap is real but not decisive — it matters if your prompts routinely run long, and is irrelevant if they sit where most production prompts sit, well under 100K. Bear in mind that filling a large window is also what makes a request expensive.
Throughput is close enough to ignore — 89/100 versus 88/100. Neither model will feel noticeably quicker in an interactive product, so latency is not a reason to choose between them.
One practical asymmetry: Claude Sonnet 5 offers a batch API at 50% off standard rates, and Grok 4.5 does not. For anything that does not need an answer immediately — nightly enrichment, backfills, evaluation runs — that discount can be worth more than the difference in list price, and it is easy to overlook when comparing headline rates.
Neither model is the obvious answer. Claude Sonnet 5 leads on benchmarks, Grok 4.5 on cost, and the gap is small on both. Run the calculator above with your real token mix — for most workloads that decides it faster than any benchmark table will.
What you actually pay
The list price is only the start. Prompt caching, batch processing and long prompts change the bill, and each provider sets them differently. Prices per 1M tokens.
| Pricing term | Claude Sonnet 5 | Grok 4.5 |
|---|---|---|
| List price (input / output) | $2.00 / $10.00 | $2.00 / $6.00 |
| Cached input | $0.2010% of the input price | $0.3015% of the input price |
| Batch API | 50% off input and output | Not on the price page |
| Long prompts | No surcharge across the 1M window | From 200K tokens: $4.00 / $12.00 |
| Input with 80% cache hits | $0.56 | $0.64 |
With 80% of input served from the cache, Grok 4.5 costs 20% less than Claude Sonnet 5 for the same input text, counting each model's tokenizer.The tokenizer factor for Claude Sonnet 5, Grok 4.5 is our estimate until it is measured.
The last row assumes 80% of input tokens are read from the cache, as in a chat app that re-sends a long system prompt or RAG over the same documents. Cache-write and storage charges are not included.
Claude also bills cache writes: 1.25× the input price for a 5-minute cache, 2× for one hour.
Checked on October 8, 2026 against the pricing pages of Anthropic, xAI.
Capability scores
iOPTERA editorial scores across 5 categories — informed by public benchmarks, not measured by us
Coding
Reasoning
Extraction
Creative
Vision
Speed Score
Context Window
What Is a Token?
Models don't read words — they process tokens.
A token is roughly 4 characters of English text (~¾ of a word). Your API bill is priced per million tokens — understanding this directly reduces your costs.
Short phrase
"Hello, world!"
- Claude Sonnet 5
- $1.14
- Grok 4.5
- $0.80
Business email
One typical email (~200 words)
- Claude Sonnet 5
- $77.22
- Grok 4.5
- $54.00
Code file
50-line Python script
- Claude Sonnet 5
- $114.40
- Grok 4.5
- $80.00
Prices shown are for 100,000 runs of each workload — one run costs a fraction of a cent on both Claude Sonnet 5 and Grok 4.5, so the number only becomes meaningful at production volume. Input tokens only; add your output volume in the calculator below.
How to check your token usage
response.usage.total_tokensEvery API response includes a usage object. Sum total_tokens across all calls to get your monthly figure, then use the calculator below.
Your Cost Calculator
Enter your actual monthly token usage to see real savings
Quick Presets
Claude Sonnet 5
$188.76/mo
$2,265.12/yr
Grok 4.5
$96.00/mo
$1,152.00/yr
Annual Savings
$1,113.12 saved per year
Grok 4.5 cheaper · $92.76/mo
Related Comparisons
Explore similar model pairs to find your best fit
Claude SonnetvsClaude Fable
$2.00 · $10.00/M input
Claude SonnetvsClaude Opus
$2.00 · $5.00/M input
Claude SonnetvsGPT-5.6 Terra
$2.00 · $2.00/M input
Claude SonnetvsGPT-5.2
$2.00 · $1.75/M input
Claude SonnetvsGemini 3.1
$2.00 · $2.00/M input
Claude SonnetvsGPT-4o
$2.00 · $2.50/M input
Grok 4.5vsGPT-5.6 Sol
$2.00 · $4.00/M input
Grok 4.5vsGPT-5.6 Terra
$2.00 · $2.00/M input