Skip to main content
BenchLM
Data

Claude Haiku 4.5 vs Mercury 2.5

Updated October 23, 2026. Rank says Claude Haiku 4.5 is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.

Share or export
Share on XLinkedInAPI/MCP

Decision reading

Claude Haiku 4.5 has the higher public point estimate, 41.07 versus 33.38. Their conditional score ranges overlap. These ranges do not establish rank confidence. 1 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

Model A
Anthropic logo

Anthropic

41.07/100

Estimated · Public rank #131

Conditional range 31.4–50.8

Model B
Inception logo

Inception

33.38/100

Estimated · Public rank #166

Conditional range 19.0–47.7

Shared results
1
Claude Haiku 4.5 only
9
Mercury 2.5 only
5
Like-for-like categories
1 / 8
Estimated: Claude Haiku 4.5 and Mercury 2.5. Conditional ranges do not establish rank confidence.How the comparison works

Which one for your work

Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.

  • Agentic work

    Tool use, computer use, and multi-step task completion

    Claude Haiku 4.5

    Claude Haiku 4.5 has the higher public agentic point estimate, 21.4 to 12, with Supported evidence for both models. The conditional ranges do not establish rank confidence.

    Confidence: limited
  • Long documents

    Prompts that approach the documented context limit

    Mercury 2.5

    Mercury 2.5 has the larger documented context window.

    Confidence: documented
  • Chat turn cost

    1K fresh input + 500 output tokens

    Mercury 2.5

    Mercury 2.5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates
Show secondary and unsupported calls
  • Repository review cost

    50K fresh input + 3K output tokens

    Mercury 2.5

    Mercury 2.5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates
  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    Mercury 2.5 is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like.

    Confidence: limited
  • Cache-heavy agent loop cost

    200K cached + 20K fresh input + 10K output tokens

    Not enough matched evidence

    The page does not recommend a cost winner because at least one model cannot fit the stated workload in one request. Claude Haiku 4.5 does not fit this workload in one request.

    Confidence: listed-rates

Which one for a specific job

Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.

The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.

16.8Claude Haiku 4.516.1Mercury 2.5

Directional only · BenchAlign v5.8

Claude Haiku 4.5 has the higher coding point estimate. Conditional score ranges do not establish rank confidence.

Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.

Same basis rules as the category table below

What is actually comparable

Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.

2 categories rest on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.

Shape of the matched evidence

Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.

A shared-evidence shape is not available.

BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.

Agentic

Like-for-like
Claude Haiku 4.5
21.4
Supported · #111/132
Mercury 2.5
12.0
Supported · #123/132
Basis
BenchAlign v5.8 lane · 3 vs 3 public rows
Reading
Claude Haiku 4.5 leads · intervals overlap

Coding

Directional only
Claude Haiku 4.5
16.8
Supported · #129/153
Mercury 2.5
16.1
Estimated · #133/153
Basis
BenchAlign v5.8 lane · 4 vs 1 public rows
Reading
Directional only

Knowledge

Directional only
Claude Haiku 4.5
32.8
Estimated · #144/187
Mercury 2.5
33.8
Supported · #139/187
Basis
BenchAlign v5.8 lane · 2 vs 1 public rows
Reading
Directional only

Reasoning

Not comparable
Claude Haiku 4.5
Not ranked
Mercury 2.5
71.7
Unranked · 2 rankable rows
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
Claude Haiku 4.5
Not ranked
Mercury 2.5
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multilingual

Not comparable
Claude Haiku 4.5
Not ranked
Mercury 2.5
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
Claude Haiku 4.5
Not ranked
Mercury 2.5
81.1
#60/153
Basis
Provisional lane · 0 vs 1 weighted rows
Reading
Not comparable

Math

Not comparable
Claude Haiku 4.5
Not ranked
Mercury 2.5
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

Supported evidence per lane · bars run 0–100Methodology

What each workload costs

Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.

Chat turn

1K fresh input + 500 output tokens

Claude Haiku 4.5
$0.0035
Fits in one request
Mercury 2.5
$0.00012
Fits in one request

Mercury 2.5 has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

Claude Haiku 4.5
$0.065
Fits in one request
Mercury 2.5
$0.00245
Fits in one request

Mercury 2.5 has the lower modeled cost

Costs use the listed standard API rates.

Cache-heavy agent loop

200K cached + 20K fresh input + 10K output tokens

Claude Haiku 4.5
$0.09
Does not fit in one request
Mercury 2.5
$0.0031
Fits in one request

Claude Haiku 4.5 does not fit this workload in one request.

Cached input falls back to the list input rate only where a cached rate is unpublished

Specification differences

Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.

Documented inputs

Claude Haiku 4.5

Not sourced

Mercury 2.5

Not sourced

Documented outputs

Claude Haiku 4.5

Not sourced

Mercury 2.5

Not sourced

Provider availability

Claude Haiku 4.5

Not sourced

Mercury 2.5

Not sourced

Reasoning profile

Claude Haiku 4.5

Non-Reasoning

Mercury 2.5

Reasoning

Weight access

Claude Haiku 4.5

Proprietary

Mercury 2.5

Proprietary

License

Claude Haiku 4.5

Proprietary

Mercury 2.5

Proprietary

Release date

Claude Haiku 4.5

2025-10-15

Mercury 2.5

2026-09-08

If you already use one of these models

Deployment change
The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
Quality signal
Claude Haiku 4.5 has the higher public point estimate, 41.07 versus 33.38. Their conditional score ranges overlap. These ranges do not establish rank confidence.
Workload cost
Repository review: $0.065 vs $0.00245. Cache-heavy agent loop: $0.09 vs $0.0031.
Context tradeoff
Mercury 2.5 has the larger documented window (260K).
Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, Claude Haiku 4.5 or Mercury 2.5?

Claude Haiku 4.5 has the higher public point estimate, 41.07 versus 33.38. Their conditional score ranges overlap. These ranges do not establish rank confidence. The page therefore keeps the decision tied to the specific documented workload.

Which is better for coding, Claude Haiku 4.5 or Mercury 2.5?

Claude Haiku 4.5 scores higher for coding on the public lane, 16.8 to 16.1. Mercury 2.5 is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like. BenchLM does not name a winner for coding from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which is better for agentic tasks, Claude Haiku 4.5 or Mercury 2.5?

Claude Haiku 4.5 has the higher public agentic tasks point estimate, 21.4 to 12, with Supported evidence for both models. The conditional ranges do not establish rank confidence.

Which costs less, Claude Haiku 4.5 or Mercury 2.5?

For the stated presets, chat costs $0.0035 on Claude Haiku 4.5 and $0.00012 on Mercury 2.5; repository review costs $0.065 and $0.00245; the cache-heavy agent loop costs $0.09 and $0.0031. Claude Haiku 4.5 does not fit this workload in one request.

Which has the larger context window, Claude Haiku 4.5 or Mercury 2.5?

Mercury 2.5 has the larger documented context window: 260K, compared with 200K.

Benchmark evidence

The full public result ledger is available for audit without forcing a wide desktop table onto a phone.

Browse raw public benchmark evidence15 rows

Agentic

  • JobBench

    Claude Haiku 4.516.0%
    Source
    Mercury 2.5—

    Not directly comparable

  • Terminal-Bench 2.1 (Vals)

    Claude Haiku 4.543.8%
    Source
    Mercury 2.534.5%
    Source

    Claude Haiku 4.5 leads this result

  • MazeBench

    Claude Haiku 4.50%
    Source
    Mercury 2.5—

    Not directly comparable

  • τ³-bench results

    Claude Haiku 4.5—
    Mercury 2.596.0%
    Source

    Not directly comparable

  • DeepSearchQA

    Claude Haiku 4.5—
    Mercury 2.534.0%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude Haiku 4.573.3%
    Source
    Mercury 2.5—

    Not directly comparable

  • VulcanBench v3

    Claude Haiku 4.576.2%
    Source
    Mercury 2.5—

    Not directly comparable

  • LiveCodeBench (Vals)

    Claude Haiku 4.541.2%
    Source
    Mercury 2.5—

    Not directly comparable

  • SWE-bench (Vals)

    Claude Haiku 4.566.6%
    Source
    Mercury 2.5—

    Not directly comparable

  • SciCode

    Claude Haiku 4.5—
    Mercury 2.538%
    Source

    Not directly comparable

Multimodal

  • ParseBench

    Claude Haiku 4.545.17%
    Source
    Mercury 2.5—

    Not directly comparable

Knowledge

  • GPQA Diamond (Vals)

    Claude Haiku 4.572.2%
    Source
    Mercury 2.5—

    Not directly comparable

  • MMLU-Pro (Vals)

    Claude Haiku 4.578.7%
    Source
    Mercury 2.5—

    Not directly comparable

  • GPQA-D

    Claude Haiku 4.5—
    Mercury 2.579.0%
    Source

    Not directly comparable

Instruction following

  • IFBench

    Claude Haiku 4.5—
    Mercury 2.577%
    Source

    Not directly comparable

15 public results · 1 shared

Watch Claude Haiku 4.5 vs Mercury 2.5

One weekly email when material rank, price, or benchmark evidence changes make this matchup worth revisiting.

Read a sample issue

Join 5,600+ readers.

Last updated October 23, 2026