Migrating from claude-sonnet-4-5-20250929 to claude-sonnet-5-5

What changes when you move from claude-sonnet-4-5-20250929 to claude-sonnet-5-5: input price −33.3%, output price −33.3%, context window 200,000 → 1,000,000 tokens.

From: claude-sonnet-4-5-20250929
Status: Deprecated
Shutdown: Nov 30, 2026
Time left: 46 days

To: claude-sonnet-5-5
Status: Active
Shutdown: not before Sep 28, 2027
Time left: —

Prices

USD per 1M tokens, standard tier

Type	claude-sonnet-4-5-20250929	claude-sonnet-5-5	Change
Input	$3.00first seen October 1, 2026 · source	$2.00first seen October 1, 2026 · source	−33.3%
Cached input	$0.30first seen October 1, 2026 · source	$0.10first seen October 8, 2026 · source	−66.7%
Output	$15.00first seen October 1, 2026 · source	$10.00first seen October 1, 2026 · source	−33.3%

At 1M input and 250K output tokens a month: $6.75 on claude-sonnet-4-5-20250929, $4.50 on claude-sonnet-5-5 (−33.3%).

Other tiers, prompt-size bands and modalities are on each model's page.

Limits

Tokens

Limit	claude-sonnet-4-5-20250929	claude-sonnet-5-5	Change
Context window	200,000 tokensin place when tracking began (October 6, 2026) · source	1,000,000 tokensin place when tracking began (October 6, 2026) · source	+400%
Max output tokens	64,000 tokensin place when tracking began (October 6, 2026) · source	128,000 tokensin place when tracking began (October 6, 2026) · source	+100%

Benchmarks

Same benchmark and source on both sides; settings named where they differ

Benchmark	claude-sonnet-4-5-20250929	claude-sonnet-5-5	Change
Arena TextArena, xhigh effort (vs high effort 32k). Ranges don't overlap.	1456 ±3	1475 ±8	+19
Arena Text: CodingArena, xhigh effort (vs high effort 32k).	1519 ±5	1527 ±15	+8 within range
Arena WebDevArena, xhigh effort (vs high effort 32k). Ranges don't overlap. Other settings not rated → 1713 ±10 high effort	1393 ±8	1774 ±14	+381
FrontierMath Tier 4Epoch AI, max effort (vs 32k).	2.4%	80.5%	+78.1 pts
FrontierMath Tiers 1-3Epoch AI, max effort (vs 32k).	23.9%	88.8%	+64.9 pts
GPQA DiamondEpoch AI, max effort (vs 59k).	82.3%	95.6%	+13.3 pts
OTIS Mock AIME 2024-2025Epoch AI, max effort (vs 59k).	77.8%	100.0%	+22.2 pts
SimpleQA VerifiedEpoch AI, max effort (vs 59k).	30.7%	46.5%	+15.8 pts

A score from one source is never compared with another source's, and company-reported scores are compared only within the same company; settings named where they differ. Data: Arena (arena.ai), CC BY 4.0; Epoch AI, Capabilities & benchmarking (epoch.ai/benchmarks), CC BY.

Features and parameters

Compare models

Same on both

Prompt caching: supported on both.claude-sonnet-4-5-20250929: in place when tracking began (October 6, 2026) · source · claude-sonnet-5-5: in place when tracking began (October 6, 2026) · source
Batch API: supported on both.claude-sonnet-4-5-20250929: in place when tracking began (October 6, 2026) · source · claude-sonnet-5-5: in place when tracking began (October 6, 2026) · source
Image input: supported on both.claude-sonnet-4-5-20250929: in place when tracking began (October 6, 2026) · source · claude-sonnet-5-5: in place when tracking began (October 6, 2026) · source
Reasoning / thinking: supported (thinking: extended; effort: not supported) on claude-sonnet-4-5-20250929, supported (thinking: adaptive; default effort: high) on claude-sonnet-5-5.claude-sonnet-4-5-20250929: in place when tracking began (October 6, 2026) · source · claude-sonnet-5-5: in place when tracking began (October 6, 2026) · source

Not published for claude-sonnet-4-5-20250929: Structured outputs, Function calling, PDF input, Fine-tuning, Built-in web search, temperature parameter, top_p parameter, logprobs.

Not published for claude-sonnet-5-5: Structured outputs, Function calling, PDF input, Fine-tuning, Built-in web search, logprobs.

Aliases

All aliases

Aliases pointing at claude-sonnet-4-5-20250929: claude-sonnet-4-5 (in place when tracking began (October 6, 2026) · source)

No aliases point at claude-sonnet-5-5.

On cloud platforms

All platform dates

Model	Platform	Platform ID	Shutdown	Time left
claude-sonnet-4-5-20250929	Amazon Bedrock	anthropic.claude-sonnet-4-5-20250929-v1:0	Apr 8, 2027Legacy	175 days
claude-sonnet-4-5-20250929	Microsoft Foundryversion 1	claude-sonnet-4-5	Nov 30, 2026Active	46 days
claude-sonnet-5-5	Amazon Bedrock	anthropic.claude-sonnet-5-5	not before Sep 28, 2027Active

Read daily from each platform's own pages. The status above uses each company's own date. Time left counts to 00:00 UTC on the shutdown date, which is the evening before in ET.

Checklist

Change the model string from claude-sonnet-4-5-20250929 to claude-sonnet-5-5.

Time until shutdown

45days

11hours

23min

53sec

Counting to 7:00 pm ET on November 29, 2026, which is 00:00 UTC on November 30, 2026.

Compared from AIWire's published data when this page loaded. Each fact links to the page it came from. Model pages: claude-sonnet-4-5-20250929, claude-sonnet-5-5.