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Model Comparison

Claude Haiku 5.5 vs Gemini 3.5 FlashWhich Is Better in 2026?

Claude Haiku 5.5 vs Gemini 3.5 Flash: which should you choose in 2026?

Claude Haiku 5.5 (by Anthropic) and Gemini 3.5 Flash (by Google) are compared below. Here is how they stack up on benchmarks, price, and capabilities, and which one to pick in 2026.

There are not enough shared, protocol-compatible benchmark results to declare a performance leader.

At least one model uses context-dependent token-pricing tiers, so the published base rates do not support an unconditional blended price comparison.

Choose Claude Haiku 5.5 if…

  • • your own prompt tests favor its output; shared comparable evidence does not identify a unique advantage

Choose Gemini 3.5 Flash if…

  • • your own prompt tests favor its output; shared comparable evidence does not identify a unique advantage

The benchmark count includes only results measured with a matching benchmark version and protocol. Arena scores are shown separately. Missing, preliminary, and incompatible data is not treated as a controlled win. Published point-score comparisons are labeled separately when protocol details are incomplete. For text-output models, the verdict also compares token pricing and context windows.

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Performance benchmarks

Every value links to its source. A dash means that no reviewed result is available for that exact model and protocol.

Claude Haiku 5.5 and Gemini 3.5 Flash benchmark results
BenchmarkClaude Haiku 5.5Gemini 3.5 Flash
AutomationBench-AA

A 657-task benchmark of multi-step work across simulated SaaS applications in six business domains. The Artificial Analysis protocol reports a guardrail-aware score and is distinct from both the public Zapier split and the unrelated dynamic AutoBench framework.

Guardrail-aware score

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BrowseComp

A benchmark of difficult, verifiable information-seeking questions designed to measure an agent's ability to locate hard-to-find facts through web browsing.

Accuracy

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OSWorld-Verified

A verified computer-use benchmark in which multimodal agents operate desktop applications and are graded from the resulting environment state.

Mean task reward

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DeepSWE 1.1

A long-horizon software-engineering benchmark with 113 original tasks graded by hand-written tests.

Pass@1

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37.0%±2.0
DataCurve
SWE-Bench Verified

A human-validated subset of real GitHub issues used to measure whether a coding agent can produce repository patches that resolve the associated tests.

Resolved

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Terminal-Bench 2.1

Version 2.1 of the benchmark for completing realistic tasks in terminal environments. Harness, resource limits, and attempt count are part of the protocol.

Mean task success

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AutoBench

A dynamic LLM evaluation framework in which models generate questions, answer them, and participate in reciprocal peer assessment. AutoBench is distinct from Zapier's AutomationBench.

Weighted peer-assessment score

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GPQA Diamond

The highest-quality subset of Graduate-Level Google-Proof Q&A, designed to test expert-level scientific reasoning in biology, physics, and chemistry.

Accuracy

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Humanity's Last Exam

A 2,500-question expert-level benchmark spanning dozens of academic fields. Tool-assisted and no-tools results are separate protocols and must not be merged.

Accuracy

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LiveBench

A contamination-resistant benchmark refreshed on a fixed release cadence. Scores from different LiveBench releases must never be compared as the same protocol.

Mean of category averages

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Pricing, capabilities, and model facts

Claude Haiku 5.5 and Gemini 3.5 Flash model facts
FeatureClaude Haiku 5.5Gemini 3.5 Flash
Context & model facts
DeveloperAnthropicGoogle
API providerAnthropicGoogle
Input context1,000,000 tokens1,048,576 tokens
Maximum output128,000 tokens65,536 tokens
Released——
Added to WritingmateOct 7, 2026May 19, 2026
LicenseNot availableNot available
Knowledge cutoff—2025-01-01
Capabilities
InputsText, Image, FileText, Image, Video, File, Audio
OutputsTextText
Provider endpoint accepts tool parametersYesYes
ReasoningYesYes
VisionYesYes
Image GenerationNoNo
Video GenerationNoNo
API pricing
Base input (per 1M tokens)$0.10$1.50
Base output (per 1M tokens)$0.50$9.00
Higher-context pricing tiers
  • ≥100,000 prompt tokens$0.50 input · $2.50 output per 1M
Base rate only
Price-comparison caveatAt least one model changes token rates above a prompt-token threshold. Base rates are shown, but an unconditional blended price ratio would not be like-for-like.
API performance
p95 latencyNot measuredNot measured
Output throughputNot measuredNot measured
Writingmate shows API performance only when both models have enough observations from the same measurement window, prompt profile, and provider. Third-party latency values are not copied into this table.

Data sources

  • Writingmate model catalog (pricing, limits, and availability)

Catalog data last updated Oct 7, 2026.

Why Pay for Multiple Subscriptions?

Comparing Claude Haiku 5.5 from Anthropic with Gemini 3.5 Flash from Google? Instead of managing separate API keys and subscriptions, get both with Writingmate.

Subscription-plan access for Claude Haiku 5.5 and Gemini 3.5 Flash
PlanPriceClaude Haiku 5.5Gemini 3.5 FlashAI ImagesAI Video
Writingmate Pro
Most popular
$20/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreVEO 3.1, Kling 3.0
Writingmate Ultimate
Power users
$60/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreVEO 3.1, Kling 3.0

Claude Haiku 5.5 vs Gemini 3.5 Flash FAQ

Which is better, Claude Haiku 5.5 or Gemini 3.5 Flash?

There are not enough shared, protocol-compatible benchmark results to declare a performance leader. At least one model uses context-dependent token-pricing tiers, so the published base rates do not support an unconditional blended price comparison.

Which model is cheaper to use through an API?

At least one model uses context-dependent token-pricing tiers, so the published base rates do not support an unconditional blended price comparison.

Which model supports more context?

The published context windows are close enough that this page does not treat the difference as a material advantage.

Can I switch between Claude Haiku 5.5 and Gemini 3.5 Flash?

Yes. Use the model selector on this page to open any current Writingmate model comparison. You can also run the same prompt with both models in Writingmate.