Claude Sonnet 4.5
Anthropic · released Sep 29, 2025
- Type
- Closed
- Input
- $3.00
- Output
- $15.00
- Cached
- $0.30
List price · per 1M tokens · Anthropic at 1M context · machine-readable source ↗
Our take
Written Sep 17, 2026Claude Sonnet 4.5 is a hosted-only model for text, images and files: we list no download for it, so using it means choosing a host. It is strongest on software engineering work, where it resolved 74.8% of real GitHub issues end-to-end inside the Sonar Foundation Agent harness.
Pick it for software engineering work where fixes must land in an existing codebase, or for long-document work where splitting files is a nuisance. Every listed offer sits at the same rate except two that run higher, so the host you choose barely changes the bill. Skip it if you need to run the model on your own hardware, or if maths and web-app building are the work you have in mind.
The case for it
- Resolved 74.8% of real GitHub issues end-to-end on SWE-bench Verified, measured inside the Sonar Foundation Agent harness, so the figure reflects the model working within that scaffold rather than alone.
- The request capacity is large enough that long documents need not be split up first, though reliable recall across all of it is unverified in our data.
- Text, images and files go into the same request, so a screenshot or a document does not have to be transcribed first.
The case against it
- We list no download for it, so using it means choosing a host and paying per token.
- Its 48.7% pass on contamination-free competitive programming problems covers self-contained exercises rather than fixes inside an existing codebase.
- On the Arena boards, maths and web-app building sit among its lower preference scores while coding is among its stronger ones; these are human preference ratings, not correctness measures.
How good is it?
A closed text model from Anthropic for drafting prose and writing code, with no weak spots flagged on the board.
- drafts, rewrites and editingArena Creative Writing · 22nd of 168
- writing and completing codeArena Coding · 36th of 168
EverydayGeneral questions and everyday reasoning
Arena Text (overall)44th of 168 · 1455
Also on this board: 1457 (Sep 25, 2026), 1456 (Aug 10, 2026). Read the pair, not the higher one.
CodingWriting and fixing code on its own
Arena Coding36th of 168 · 1512
Also on this board: 1519 (Sep 25, 2026), 1519 (Aug 10, 2026). Read the pair, not the higher one.
AgenticPlanning, calling tools, staying on task
Not yet scored on Arena Agent. It is on SWE-bench Verified, in 4th of 42 with 74.8.
WritingDrafting and rewriting prose
Arena Creative Writing22nd of 168 · 1454
Arena Creative Writing is the only board that has scored it for this.
Also on this board: 1450 (Sep 25, 2026), 1449 (Aug 10, 2026). Read the pair, not the higher one.
These tests check whether a model follows instructions — a precondition for all the work above, but not a measure of how well that work is done.
Every published score for this model9 scoresEvery figure we hold, from 9 boards, with who ran it and a link to the source — including the boards no rating above is built on.
Where to rent it
Prices checked between 57 min and 60 min ago — each listing carries its own date.
Anthropic, direct
The lab is also the cheapest we hold. The strip above and this offer are the same one, so nothing on this page undercuts Anthropic on 1M of context.
- per 1M tokens
- $3.00 in / $15.00 out
- Context served
- 1M
- Throughput
- ~42 tok/s
| Provider | In / out per 1M tokens | Context | Throughput | Trains on prompts | Logs prompts | Zero retention |
|---|---|---|---|---|---|---|
| Claude Platform on AWSThrough OpenRouter | $3.00 / $15.00checked 59 min ago | 1M64K max reply | 37 tok/s | No | Yes30 days | Unknown |
| Microsoft Azure AIglobalThrough OpenRouter | $3.00 / $15.00checked 59 min ago | 200K64K max reply | 38 tok/s | No | No | Unknown |
| Amazon BedrockThrough OpenRouter | $3.00 / $15.00checked 59 min ago | 1M64K max reply | 36 tok/s | No | No | Confirmed |
| OpenRouterOpenRouter's own listing | $3.00 / $15.00checked 60 min ago | 1M | not measured | Unknown | Unknown | Unknown |
| Google Vertex AIglobalThrough OpenRouter | $3.00 / $15.00checked 59 min ago | 1M64K max reply | 35 tok/s | No | No | Confirmed |
| AnthropicDirect | $3.00 / $15.00checked 57 min ago | 1M64K max reply | 42 tok/s | No | Yes30 days | Unknown |
| Google Vertex AIus-east5Through OpenRouter | $3.30 / $16.50checked 59 min ago | 1M64K max reply | 46 tok/s | No | No | Confirmed |
| Amazon Bedrockeu-west-1Through OpenRouter | $3.30 / $16.50checked 59 min ago | 1M64K max reply | 37 tok/s | No | No | Confirmed |
Microsoft Azure AI
Amazon Bedrock
OpenRouter
Google Vertex AIAcross the 8 listings we hold: 7 say they do not train on prompts, 0 say they do and 1 does not say. 4 appear in the zero-retention registry we check; the rest are unknown to us.
What each host's API supports
From the parameter list each endpoint publishes. Streaming is omitted: nothing we hold reports it, for any model.
| Provider | Tool calling | JSON output | Strict schema |
|---|---|---|---|
| Claude Platform on AWSThrough OpenRouter | ✓ | ✓ | ✓ |
| Microsoft Azure AIglobalThrough OpenRouter | ✓ | ✓ | ✓ |
| Amazon BedrockThrough OpenRouter | ✓ | ✓ | ✓ |
| OpenRouterOpenRouter's own listing | ✓ | ✓ | ✓ |
| Google Vertex AIglobalThrough OpenRouter | ✓ | ✗ | ✓ |
| AnthropicDirect | ✓ | ✓ | ✓ |
| Google Vertex AIus-east5Through OpenRouter | ✓ | ✗ | ✓ |
| Amazon Bedrockeu-west-1Through OpenRouter | ✓ | ✓ | ✓ |
Tool calling: 8 of 8 listings say yes. JSON output: 6 of 8 listings say yes, 2 say no. Strict schema: 8 of 8 listings say yes.
Models people weigh against Claude Sonnet 4.5
When we formed this view
Recent changes
What moved
first indexed by our pipelineWhat moved
leaderboardEach date is the day we first saw the change, or the day the maker announced it.
What we do not know about this model yet
- Nothing we hold says whether an endpoint streams, so we do not show it either way.
- 1 of 8 listings does not say whether it trains on prompts.
- We hold no batch or off-peak rate for any of its listings.
Licence and identifiers
What the licence allowsWe hold no licence record for this model. Inside are the identifiers you need to pull it — its Hugging Face repo where we have one, our slug and a machine-readable card.
Licence
We hold no licence record for this model, and no record of published weights either — so we can neither summarise its terms nor point you at the weights.
Identifiers
- Takes in, gives back
- Text, images and documents in, text out
- Catalogue slug
- anthropic-claude-sonnet-4-5