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Model comparison · Updated 17 Aug 2026

Claude Opus 4.5 vs o3

o3 is about 2.5× cheaper on input ($2.00 against $5.00 per 1M tokens) and on output. Both have a 200K-token context window. For a support chatbot at 10,000 chats a day, the standard-tier bill is about $4,500 a month for Claude Opus 4.5 and $1,620 for o3.

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ModelsAtlas. “Claude Opus 4.5 vs o3”. Retrieved 17 Aug 2026. https://modelsatlas.com/compare/anthropic/claude-opus-4-5/vs/openai/o3

Model A

Claude Opus 4.5

by Anthropic · weights not marked open · GRIDF3

Input / 1M
$5.00
asserted Vendor states
Source
docs.anthropic.com/en/docs/about-claude/pricing
Retrieved
17 Aug 2026
Output / 1M$25.00
Context200K
vs

Model B

o3

by OpenAI · weights not marked open · GRIDE3

Input / 1M
$2.00
observed We measured
Source
Our catalogue
Retrieved
17 Aug 2026
Output / 1M$8.00
Context200K

Key numbers

Standard tier · highlighted = better

Claude Opus 4.5
o3
Input / 1M tokens
$5.00
$2.00
Output / 1M tokens
$25.00
$8.00
Batch input / output
$2.50 / $12.50
$0.55 / $2.20
Context window
200,000
200,000
Input types
Not disclosed
Not disclosed
Weights
Not marked open
Not marked open
Tiers listed
batch, standard
batch, standard
Prices checked
2026-08-17
2026-08-17

What it costs for real workloads

Monthly, standard tier, 30 days

Support chatbot10k chats/day · 1.5k in, 300 out
$4,500/mo
$1,620/mo
RAG over documents2k queries/day · 12k in, 500 out
$4,350/mo
$1,680/mo
Coding agent300 tasks/day · 60k in, 8k out
$4,500/mo
$1,656/mo

Claude Opus 4.5   o3 · Derived from the standard-tier prices above, input and output tokens per request as stated, 30 days. Excludes caching discounts and batch. Try your own numbers.

On the atlas

Price band (A–H) × context band (1–6)

1 square apart. o3 (E3) sits 1 price band cheaper than Claude Opus 4.5 (F3).

Same square as Claude Opus 4.5: Claude Sonnet 4 ($3.00). Same square as o3: Claude Haiku 4.5 ($1.00), Grok Build 0.1 ($1.00), o3 Mini High ($1.10). Open F3 · Open E3

AFreeB<$0.10C$0.10–0.30D$0.30–1E$1–3F$3–10G$10–30H$30+1<32K232–128K3128–256K4256K–1M51M6>1MINPUT PRICE PER 1M TOKENS →CONTEXT WINDOW ↑ · position within a square follows the real valueClaude Sonnet 4 · F3GPT Chat Latest · F4GPT-5.4 Image 2 · F4Command A · E3Nano Banana Pro (Gemini 3 Pro Image) · E3o3 Mini High · E3o4 Mini · E3o4 Mini High · E3Claude Haiku 4.5 · E3Claude Opus 4.5Claude Opus 4.5o3o3
Claude Opus 4.5o3Nearest neighboursOpen weights
View the map as a table (3 squares)
SquarePrice bandContext bandModels
GRIDE3$1–3128–256Ko3, Command A, Nano Banana Pro (Gemini 3 Pro Image), o3 Mini High, o4 Mini, o4 Mini High, Claude Haiku 4.5
GRIDF3$3–10128–256KClaude Opus 4.5, Claude Sonnet 4
GRIDF4$3–10256K–1MGPT Chat Latest, GPT-5.4 Image 2

Capabilities side by side

Only what our records list

Claude Opus 4.5
o3
Vision input
Not disclosed
Not disclosed
Audio input
Not disclosed
Not disclosed
Open weights
Not marked open
Not marked open
Batch tier
Supported
Supported
Free tier
Not listed
Not listed
Thinking tier
Not listed
Not listed

Neither record lists input types, so we do not claim any.

Which should you choose?

Editorial

Choose Claude Opus 4.5 if…

Nothing in the recorded numbers favours Claude Opus 4.5 over o3. Pick it for what our records do not cover — your own tests, or an account you already have with Anthropic.

Choose o3 if…

  • you pay by the token: it costs $2.00 per 1M input against $5.00
  • output dominates your bill: $8.00 per 1M output against $25.00

Each reason is a fact from the tables above. Picking between them is our judgement, and we do not benchmark quality: price and context are what we can measure, so test both on your own prompts before you commit.

Questions

Is Claude Opus 4.5 better than o3?
We do not benchmark quality, so we cannot say. On the recorded numbers: o3 is about 2.5× cheaper on input ($2.00 against $5.00 per 1M tokens) and on output. Both have a 200K-token context window. For a support chatbot at 10,000 chats a day, the standard-tier bill is about $4,500 a month for Claude Opus 4.5 and $1,620 for o3. Which is better for you depends on your task; test both on your own prompts.
Which is cheaper, Claude Opus 4.5 or o3?
o3: $2.00 against $5.00 per 1M input tokens, and $8.00 against $25.00 per 1M output, on standard pricing.
How much does each cost per 1M tokens?
Claude Opus 4.5: $5.00 input and $25.00 output. o3: $2.00 input and $8.00 output. Standard tier, USD.
Which has the larger context window?
Neither: both have 200,000 tokens.
Do both offer batch pricing?
Claude Opus 4.5 lists a batch tier, at 50% of its standard price. o3 lists a batch tier, at 50% of its standard price.
Can both read images or audio?
Input types recorded for Claude Opus 4.5: none recorded. For o3: none recorded. Where a record lists none we say so rather than guess; check each vendor's documentation before relying on a capability.
Is either model open-weight?
Claude Opus 4.5: not marked open-weight in our records. o3: not marked open-weight in our records.
What would each cost for a support chatbot?
At 10,000 chats a day, 1,500 input and 300 output tokens each, 30 days, standard tier: about $4,500 a month for Claude Opus 4.5 and $1,620 for o3. This is our calculation from the listed prices, not a quote.

About the two models

Claude Opus 4.5

By Anthropic. $5.00 input and $25.00 output per 1M tokens, 200K context, atlas square F3. Tiers listed: batch, standard.

Full specs & pricing →

o3

By OpenAI. $2.00 input and $8.00 output per 1M tokens, 200K context, atlas square E3. Tiers listed: batch, standard.

Full specs & pricing →

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