Cost and performance comparison
Claude 3 Opus vs Claude 3.5 Sonnet
Model AAnthropic
Claude 3 Opus
- Cost / 1M Tokens
- $33.00
- 70% in · 30% out mix
- ≈ $36.30 for the same text, tokenizer included
- Value Index (score÷cost)
- 2.5
- Higher = better value
- Speed
- 50/100
- Context
- 200K
- Tier
- Power Tier
Last list price before the model was retired.
Its tokenizer produces about 10% 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.
Model BAnthropic
Claude 3.5 Sonnet
- Cost / 1M Tokens
- $6.60
- 70% in · 30% out mix
- ≈ $7.26 for the same text, tokenizer included
- Value Index (score÷cost)
- 12.3
- Higher = better value
- Speed
- 95/100
- Context
- 200K
- Tier
- Smart Tier
Last list price before the model was retired.
Its tokenizer produces about 10% 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.
In-depth analysis
Claude 3 Opus vs Claude 3.5 Sonnet: Detailed Comparison
Claude 3 Opus is Anthropic's flagship-tier language model with a 200K-token context window, excelling at reasoning. Claude 3.5 Sonnet from Anthropic is a mid-range-tier model supporting 200K tokens in context, with standout performance in creative tasks.
Claude 3.5 Sonnet is both the cheaper and the stronger model here — for the same text it costs 80% less than Claude 3 Opus and still leads on combined coding and reasoning by 7 points. There is no tradeoff to weigh on this pair: unless you need something specific from Claude 3 Opus, the cheaper model is simply the better one. Claude 3 Opus is priced at $15.00/M input tokens and $75.00/M output tokens. Claude 3.5 Sonnet costs $3.00/M input and $15.00/M output.
On iOPTERA's editorial scores, Claude 3.5 Sonnet leads with 88/100 for coding and 89/100 for reasoning, against Claude 3 Opus's 80/100 and 90/100.
Capability breakdown
Across the five core benchmark categories, here is how Claude 3 Opus and Claude 3.5 Sonnet stack up head to head:
Best model by task
- coding: Claude 3.5 Sonnet wins with 88/100
- reasoning: Claude 3 Opus wins with 90/100
- data extraction: Claude 3.5 Sonnet wins with 90/100
- creative tasks: Claude 3.5 Sonnet wins with 91/100
- vision/multimodal: Claude 3.5 Sonnet wins with 88/100
Estimated monthly cost at scale
For 10M + 2M tokens of text a month (counted the way OpenAI's tokenizer counts), Claude 3 Opus runs about $330.00 while Claude 3.5 Sonnet runs about $66.00 — Claude 3.5 Sonnet saves roughly $264.00 (80%) every month.
What actually decides it
Both models come from Anthropic, so they share a tokenizer, an API surface, and a billing account. Switching between them is a model-string change and nothing else — no new SDK, no re-tokenizing your prompts to re-estimate cost, no second vendor to onboard. That makes routing between them far cheaper to implement than a cross-vendor split.
Claude 3.5 Sonnet and Claude 3 Opus were released within 3 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.
Context is effectively a tie: 200K against 200K. Neither model unlocks a document size the other cannot handle, so this axis should not enter the decision. If you were hoping context would break the tie for you, it will not.
Latency separates them: Claude 3.5 Sonnet scores 95/100 against 50/100 for Claude 3 Opus, a 45-point gap. That matters for anything a person waits on — chat, autocomplete, interactive tools. For batch and background work it does not, and trading latency for capability there is usually the right call.
One practical asymmetry: Claude 3.5 Sonnet offers a batch API at 50% off standard rates, and Claude 3 Opus 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.
Claude 3.5 Sonnet wins this comparison outright — cheaper and stronger. Choose Claude 3 Opus only if it has a specific capability you need; on price and benchmarks it is behind on both.
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 3 Opus
- $6.60
- Claude 3.5 Sonnet
- $1.32
Business email
One typical email (~200 words)
- Claude 3 Opus
- $445.50
- Claude 3.5 Sonnet
- $89.10
Code file
50-line Python script
- Claude 3 Opus
- $660.00
- Claude 3.5 Sonnet
- $132.00
Prices shown are for 100,000 runs of each workload — one run costs a fraction of a cent on both Claude 3 Opus and Claude 3.5 Sonnet, 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 3 Opus
$1,089.00/mo
$13,068.00/yr
Claude 3.5 Sonnet
$217.80/mo
$2,613.60/yr
Annual Savings
$10,454.40 saved per year
Claude 3.5 Sonnet cheaper · $871.20/mo
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