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BenchLM
Model A
Celeris-1

Celeris

—

Evidence status unavailable

90% interval unavailable

Celeris-1 vs Claude Mythos 5

Updated August 22, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.

Model B
Claude Mythos 5

Anthropic

83.0/100

Supported · Public rank #1

90% interval 79.6–86.3

Decision reading

The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. Use the documented cost, context, and runtime rows instead.

0 results are shared. Category rows based on different benchmark sets are marked directional and do not name a winner.

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.

  • Long documents

    Prompts that approach the documented context limit

    Claude Mythos 5

    Claude Mythos 5 has the larger documented context window.

    Confidence: documented

Show secondary and unsupported calls

  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    No shared weighted benchmark basis supports a winner.

    Confidence: limited

  • Agentic work

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

    Not enough matched evidence

    No shared weighted benchmark basis supports a winner.

    Confidence: limited

  • Chat turn cost

    1K fresh input + 500 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. Celeris-1 does not fit this workload in one request.

    Confidence: listed-rates

  • 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. Celeris-1 does not fit this workload in one request. Celeris-1 has no published cached-input rate, so cached tokens use its listed input rate.

    Confidence: rate-fallback

  • Repository review cost

    50K fresh input + 3K 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. Celeris-1 does not fit this workload in one request.

    Confidence: listed-rates

What is actually comparable

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

Shared results
0
Celeris-1 only
4
Claude Mythos 5 only
15
Like-for-like categories
0 / 8

Category results, on a stated basis

Each row states whether both averages use the same weighted benchmark set. Directional and not-comparable rows remain visible, but they never receive a winner in this template.

Agentic

Not comparable
Celeris-1
Not measured
Claude Mythos 5
87.0
Weighted basis
0 vs 3 rows
Reading
Not comparable

Coding

Not comparable
Celeris-1
Not measured
Claude Mythos 5
89.7
Weighted basis
0 vs 2 rows
Reading
Not comparable

Reasoning

Not comparable
Celeris-1
Not measured
Claude Mythos 5
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Knowledge

Not comparable
Celeris-1
75.9
Claude Mythos 5
68.5
Weighted basis
1 vs 2 rows
Reading
Not comparable

Math

Not comparable
Celeris-1
Not measured
Claude Mythos 5
97.6
Weighted basis
0 vs 1 rows
Reading
Not comparable

Multilingual

Not comparable
Celeris-1
Not measured
Claude Mythos 5
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Multimodal

Not comparable
Celeris-1
Not measured
Claude Mythos 5
93.5
Weighted basis
0 vs 1 rows
Reading
Not comparable

Instruction following

Not comparable
Celeris-1
80.8
Claude Mythos 5
Not measured
Weighted basis
1 vs 0 rows
Reading
Not comparable

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.

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

Celeris-1
$0.00055
Does not fit in one request
Claude Mythos 5
$0.035
Fits in one request

Celeris-1 does not fit this workload in one request.

Repository review

50K fresh input + 3K output tokens

Celeris-1
$0.0121
Does not fit in one request
Claude Mythos 5
$0.65
Fits in one request

Celeris-1 does not fit this workload in one request.

Cache-heavy agent loop

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

Celeris-1
$0.051
Does not fit in one request
Cached input priced at the published list-input rate
Claude Mythos 5
$0.9
Fits in one request

Celeris-1 does not fit this workload in one request. Celeris-1 has no published cached-input rate, so cached tokens use its listed input rate.

Specification differences

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

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

Celeris-1

Not published

Celeris API pricing

Claude Mythos 5

$1 per 1M cached input tokens

Claude API pricing

Reasoning profile

Celeris-1

Non-Reasoning

Claude Mythos 5

Reasoning

Weight access

Celeris-1

Proprietary

Claude Mythos 5

Proprietary

License

Celeris-1

Proprietary

Claude Mythos 5

Proprietary

Release date

Celeris-1

2026-07-22

Claude Mythos 5

2026-06-09

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
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict.
Workload cost
Repository review: $0.0121 vs $0.65. Cache-heavy agent loop: $0.051 vs $0.9.
Context tradeoff
Claude Mythos 5 has the larger documented window (1M).

Run the same representative tasks against both endpoints before changing production traffic.

Benchmark evidence

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

Browse raw public benchmark evidence19 rows

Agentic

  • Terminal-Bench 2.0

    Celeris-1—
    Claude Mythos 588%
    Source

    Not directly comparable

  • OSWorld-Verified

    Celeris-1—
    Claude Mythos 585%
    Source

    Not directly comparable

  • BrowseComp

    Celeris-1—
    Claude Mythos 588%
    Source

    Not directly comparable

  • CyberGym

    Celeris-1—
    Claude Mythos 583.8%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Celeris-1—
    Claude Mythos 595.5%
    Source

    Not directly comparable

  • SWE-bench Pro

    Celeris-1—
    Claude Mythos 580.3%
    Source

    Not directly comparable

  • Terminal-Bench 2.0

    Celeris-1—
    Claude Mythos 588.0%
    Source

    Not directly comparable

Reasoning

  • DROP

    Celeris-181.4%
    Source
    Claude Mythos 5—

    Not directly comparable

Knowledge

  • MMLU-Pro

    Celeris-175.9%
    Source
    Claude Mythos 5—

    Not directly comparable

  • GPQA

    Celeris-1—
    Claude Mythos 594.1%
    Source

    Not directly comparable

  • HLE

    Celeris-1—
    Claude Mythos 564.5%
    Source

    Not directly comparable

  • HLE w/o tools

    Celeris-1—
    Claude Mythos 559%
    Source

    Not directly comparable

Math

  • GSM8K

    Celeris-193.7%
    Source
    Claude Mythos 5—

    Not directly comparable

  • USAMO 2026

    Celeris-1—
    Claude Mythos 597.6%
    Source

    Not directly comparable

Multilingual

  • SWE Multilingual

    Celeris-1—
    Claude Mythos 592.2%
    Source

    Not directly comparable

Multimodal

  • SWE-bench Multimodal

    Celeris-1—
    Claude Mythos 554.9%
    Source

    Not directly comparable

  • CharXiv

    Celeris-1—
    Claude Mythos 593.5%
    Source

    Not directly comparable

  • CharXiv w/o tools

    Celeris-1—
    Claude Mythos 588.9%
    Source

    Not directly comparable

Instruction following

  • IFEval

    Celeris-180.8%
    Source
    Claude Mythos 5—

    Not directly comparable

Frequently asked questions

Which is better, Celeris-1 or Claude Mythos 5?

The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. The page therefore keeps the decision tied to the specific documented workload.

Which is better for coding, Celeris-1 or Claude Mythos 5?

The published evidence does not provide a shared weighted coding basis for both models, so BenchLM does not name a coding winner.

Which is better for agentic tasks, Celeris-1 or Claude Mythos 5?

The published evidence does not provide a shared weighted agentic tasks basis for both models, so BenchLM does not name a agentic tasks winner.

Which costs less, Celeris-1 or Claude Mythos 5?

For the stated presets, chat costs $0.00055 on Celeris-1 and $0.035 on Claude Mythos 5; repository review costs $0.0121 and $0.65; the cache-heavy agent loop costs $0.051 and $0.9. Celeris-1 does not fit this workload in one request. Celeris-1 has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, Celeris-1 or Claude Mythos 5?

Claude Mythos 5 has the larger documented context window: 1M, compared with 131,072 tokens.

Related comparisons

Compare API pricing Read the methodology Open the model selector

Last updated August 22, 2026

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