Claude Haiku 4.5 vs Claude Opus 4.7 for Translation
Winner: Claude Haiku 4.5. In our testing Claude Haiku 4.5 scores 5.0 on Translation vs Claude Opus 4.7's 4.5, and ranks 1st vs Opus's 28th out of 53. The decisive factors are Haiku's top multilingual score (5) plus perfect faithfulness (5) in our suite, combined with much lower token costs ($1 input / $5 output per million tokens). Opus 4.7 is capable, but its lower multilingual score (4) and higher price make it the secondary choice for translation quality per dollar in our benchmarks.
anthropic
Claude Haiku 4.5
Benchmark Scores
External Benchmarks
Pricing
Input
$1.00/MTok
Output
$5.00/MTok
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anthropic
Claude Opus 4.7
Benchmark Scores
External Benchmarks
Pricing
Input
$5.00/MTok
Output
$25.00/MTok
modelpicker.net
Task Analysis
What Translation demands: accurate cross-language equivalence, idiomatic phrasing, and preservation of meaning and tone — measured here by our multilingual and faithfulness tests. In our suite the primary evidence is the task scores: Haiku 4.5 scores 5.0 on Translation and ranks 1/53; Opus 4.7 scores 4.5 and ranks 28/53. Supporting internal benchmarks show why: Haiku has a multilingual rating of 5 and faithfulness 5, signaling consistent, high-fidelity outputs across languages. Opus matches Haiku on faithfulness (5) but scores lower on multilingual (4). Other capabilities matter too: constrained rewriting (compression into hard limits) favors Opus (4 vs Haiku's 3), which helps when strict character counts are required. Both models tie on long-context handling and faithfulness in our tests, but Haiku's combination of multilingual strength and much lower cost makes it the stronger translation pick in most workflows.
Practical Examples
Where Claude Haiku 4.5 shines:
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Website localization: high-volume page sets where equivalent idiomatic phrasing and consistent terminology across pages matter; Haiku's multilingual 5 and faithfulness 5 plus $1/$5 per M-token pricing reduce cost and risk.
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Marketing copy adaptation: preserving tone and brand voice across languages with limited editing overhead thanks to strong persona consistency and multilingual scores. Where Claude Opus 4.7 shines:
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Tight character-limited outputs: translating social ads or SMS that must fit exact counts — Opus's constrained rewriting score (4 vs Haiku's 3) and rank (6th vs 32nd) make it better at compression without losing meaning.
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Very large single-document translation or monolithic corpora: Opus offers a 1,000,000 token context window and 128k max output tokens (vs Haiku's 200k / 64k), so for translating huge files in one pass Opus is preferable. Concrete numbers from our tests: Haiku Translation score 5.0 vs Opus 4.5; multilingual 5 vs 4; constrained rewriting 3 vs 4; costs $1 input / $5 output per M-token (Haiku) vs $5 / $25 (Opus).
Bottom Line
For Translation, choose Claude Haiku 4.5 if you need the best multilingual fidelity per dollar (task score 5.0, multilingual 5, faithfulness 5) and are translating lots of content affordably. Choose Claude Opus 4.7 if you must translate extremely large single files in one pass (1,000,000-token context) or require better constrained rewriting for strict character-limited outputs despite higher costs.
How We Test
We test every model against our 12-benchmark suite covering tool calling, agentic planning, creative problem solving, safety calibration, and more. Each test is scored 1–5 by an LLM judge. Read our full methodology.
For translation tasks, we supplement our benchmark suite with WMT/FLORES scores from Epoch AI, an independent research organization.