Claude Haiku 5.5

New

anthropic/claude-haiku-5.5-20261007

This model accepts text, image, and file inputs and provides text outputs. It has a context length of 1,000,000 tokens and supports tools and reasoning. Input pricing is $0.10 per million tokens, and output pricing is $0.50 per million tokens.

  • tool use
  • structured outputs
  • reasoning

At a glance

provideranthropic
releasedOct 7, 2026
context1M
input / M$0.100

Specifications

What the API gives you

Context window
1M tokens
Max output
128K tokens
Input price
$0.100 / 1M tokens
Output price
$0.50 / 1M tokens
Cache read
$0.010 / 1M tokens
Modalities
text, image, file → text
Knowledge cutoff
—
Released
Oct 7, 2026

Measured evidence

Public benchmark record

Design Arena Coding
1280 Elo2026-10-16
Design Arena UI
1300 Elo2026-10-16
Design Arena Website
1265 Elo2026-10-16
FACTS Grounding
65.8%2026-10-09evaluated 2026-10-09
FrontierMath Tiers 1-3 (Epoch AI)‡
75.1% ± 2.62026-10-07max effort, evaluated 2026-10-07
GPQA Diamond (Epoch AI)‡
89.6% ± 22026-10-09max effort, evaluated 2026-10-09
LiveBench Agentic Coding
57.2%2026-10-16
LiveBench Coding
77.9%2026-10-16
LiveBench Data Analysis
51.8%2026-10-16
LiveBench Instruction Following
54.7%2026-10-16
LiveBench Language
62.6%2026-10-16
LiveBench Math
86.4%2026-10-16
LiveBench Reasoning
84.6%2026-10-16
LMArena Agent‡
1.92026-10-14high effort
LMArena Agent Steerability‡
6.42026-10-14high effort
LMArena Agent Task Outcome‡
1.62026-10-14high effort
LMArena Agent Tool Hallucination‡
-0.72026-10-14high effort
LMArena WebDev
1585 Elo2026-10-13
OTIS Mock AIME (Epoch AI)‡
98.9% ± 0.52026-10-07xhigh effort, evaluated 2026-10-07
SimpleQA Verified (Epoch AI)‡
23.8% ± 1.32026-10-09max effort, evaluated 2026-10-09

LMArena data licensed CC-BY-4.0. Aider (Apache-2.0) and SWE-bench (MIT) are open. Design Arena uses blind human preference. ‡ Submitted scaffold plus model result. Compare the harness and effort settings, not only the model name.

Task evidence

How broad is the support?

Each status is exact to this model version and the selected task. Official release claims remain provisional.

  • Best LLM for Frontend & UIEstablished evidence

    91% of intended weighted task evidence across 3 independent sources. 6 of 6 configured evaluation feeds currently have results.

  • Best LLM for Code CompletionEstablished evidence

    79% of intended weighted task evidence across 2 independent sources. 3 of 3 configured evaluation feeds currently have results.

  • Best LLM for Competition MathEstablished evidence

    74% of intended weighted task evidence across 3 independent sources. 6 of 6 configured evaluation feeds currently have results.

  • Best LLM for Math & ReasoningEstablished evidence

    72% of intended weighted task evidence across 4 independent sources. 7 of 7 configured evaluation feeds currently have results.

  • Best LLM for Logic & Problem SolvingEstablished evidence

    64% of intended weighted task evidence across 2 independent sources. 5 of 5 configured evaluation feeds currently have results.

  • Best LLM for CodingEstablished evidence

    53% of intended weighted task evidence across 3 independent sources. 7 of 7 configured evaluation feeds currently have results.

Show all 42 tasks
  • Best LLM for a General AssistantEstablished evidence

    50% of intended weighted task evidence across 2 independent sources. 6 of 6 configured evaluation feeds currently have results.

  • Best LLM for Grounded RAGEstablished evidence

    48% of intended weighted task evidence across 2 independent sources. 5 of 7 configured evaluation feeds currently have results.

  • Best Local LLM for CodingEstablished evidence

    47% of intended weighted task evidence across 2 independent sources. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for Document SummarizationEstablished evidence

    45% of intended weighted task evidence across 2 independent sources. 5 of 6 configured evaluation feeds currently have results.

  • Best LLM for SummarizationEstablished evidence

    45% of intended weighted task evidence across 2 independent sources. 5 of 6 configured evaluation feeds currently have results.

  • Best LLM for Autonomous AgentsEstablished evidence

    36% of intended weighted task evidence across 2 independent sources. 6 of 6 configured evaluation feeds currently have results.

  • Best LLM for AI AgentsEstablished evidence

    34% of intended weighted task evidence across 2 independent sources. 9 of 9 configured evaluation feeds currently have results.

  • Best LLM for Debugging & Code ReviewEstablished evidence

    33% of intended weighted task evidence across 2 independent sources. 5 of 5 configured evaluation feeds currently have results.

  • Best LLM for Agentic CodingEstablished evidence

    26% of intended weighted task evidence across 2 independent sources. 7 of 7 configured evaluation feeds currently have results.

  • Best LLM for Creative WritingProvisional evidence

    44% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Creative Writing or LMArena Text. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for WritingProvisional evidence

    44% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Creative Writing or LMArena Text. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for Fast SummariesProvisional evidence

    42% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or Route reliability. 2 of 3 configured evaluation feeds currently have results. Official release evidence is also tracked provisionally.

  • Best LLM for Tool & Function CallingProvisional evidence

    38% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or LMArena Search. 6 of 7 configured evaluation feeds currently have results.

  • Best Open-Weight LLM for Self-HostingProvisional evidence

    36% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or Route reliability. 2 of 3 configured evaluation feeds currently have results.

  • Best LLM for Chat & RoleplayProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Creative Writing or LMArena Text. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for Roleplay & CharacterProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Creative Writing or LMArena Text. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for Business WritingProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Creative Writing or LMArena Instruction Following. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for Literary TranslationProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or WMT translation. 3 of 4 configured evaluation feeds currently have results.

  • Best LLM for Marketing CopyProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Creative Writing or LMArena Instruction Following. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for Everyday TranslationProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or WMT translation. 3 of 4 configured evaluation feeds currently have results.

  • Best LLM for TranslationProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or WMT translation. 3 of 4 configured evaluation feeds currently have results.

  • Best Value LLMProvisional evidence

    33% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or Route reliability. 2 of 3 configured evaluation feeds currently have results.

  • Best Cheap LLM for High VolumeProvisional evidence

    30% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or Route reliability. 2 of 3 configured evaluation feeds currently have results. Official release evidence is also tracked provisionally.

  • Cheapest Capable LLMProvisional evidence

    30% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Text or Route reliability. 2 of 3 configured evaluation feeds currently have results.

  • Best LLM for Hermes AgentProvisional evidence

    29% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or SWE-rebench. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for OpenHandsProvisional evidence

    29% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or SWE-rebench. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for GooseProvisional evidence

    29% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or SWE-rebench. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for OpenClawProvisional evidence

    29% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or SWE-rebench. 4 of 4 configured evaluation feeds currently have results.

  • Best LLM for JSON & Schema OutputProvisional evidence

    24% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or LMArena Text. 3 of 4 configured evaluation feeds currently have results.

  • Best LLM for Structured Data ExtractionProvisional evidence

    24% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or LMArena Text. 3 of 4 configured evaluation feeds currently have results. Official release evidence is also tracked provisionally.

  • Best LLM for RAG & Long ContextProvisional evidence

    22% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Document or LMArena Long Query. 5 of 6 configured evaluation feeds currently have results. Official release evidence is also tracked provisionally.

  • Best LLM for High-Volume ExtractionProvisional evidence

    21% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Route reliability or Structured-output eval. 1 of 3 configured evaluation feeds currently have results. Official release evidence is also tracked provisionally.

  • Best LLM for Computer & Browser UseProvisional evidence

    17% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Berkeley Function Calling or OSWorld Verified. 3 of 3 configured evaluation feeds currently have results. Official release evidence is also tracked provisionally.

  • Best LLM for Image UnderstandingProvisional evidence

    11% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LMArena Vision or VLMEvalKit tasks. 2 of 3 configured evaluation feeds currently have results.

  • Best LLM for Charts & DiagramsProvisional evidence

    Official release evidence found; independent confirmation is still missing from LMArena Document or LMArena Vision.

  • Best LLM for Document ParsingProvisional evidence

    Official release evidence found; independent confirmation is still missing from LMArena Document or LMArena Vision.

Official release evidence · provisional

What the launch material actually says

Verbatim claims from the model provider. These help on launch day but do not count as independent confirmation.

Recommendation coverage

Where this model appears

  1. #8Best LLM for Autonomous Agents

Catalog data via OpenRouter and models.dev. Last checked within the past 6 hours.