Skip to main content
BenchLM

Claude Sonnet 4.5 vs Gemini 3.1 Flash-Lite

Updated September 23, 2026. Rank cannot separate these two. Price, access, and your workload decide. Public scores include evidence status and uncertainty.

Share or export
Share on XLinkedInSocial cardCSVJSON

Decision reading

Claude Sonnet 4.5 has the higher public score estimate, 47.86 versus 47.46, but the 90% score intervals overlap. Treat that as a lead, not a settled winner. 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

47.86/100

Estimated · Public rank #85

90% interval 42.153.6

Model B
Google logo

Google

47.46/100

Estimated · Public rank #86

90% interval 36.058.9

Shared results
1
Claude Sonnet 4.5 only
10
Gemini 3.1 Flash-Lite only
7
Like-for-like categories
0 / 8
Estimated: Claude Sonnet 4.5 and Gemini 3.1 Flash-LiteHow 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.

  • Long documents

    Prompts that approach the documented context limit

    Gemini 3.1 Flash-Lite

    Gemini 3.1 Flash-Lite has the larger documented context window.

    Confidence: documented
  • Chat turn cost

    1K fresh input + 500 output tokens

    Gemini 3.1 Flash-Lite

    Gemini 3.1 Flash-Lite 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

    Gemini 3.1 Flash-Lite

    Gemini 3.1 Flash-Lite 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

    Claude Sonnet 4.5 is not ranked on the public lane for coding, so no winner is named for coding.

    Confidence: limited
  • Agentic work

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

    Not enough matched evidence

    Claude Sonnet 4.5 and Gemini 3.1 Flash-Lite are scored on Estimated evidence for agentic, 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 Sonnet 4.5 does not fit this workload in one request. Claude Sonnet 4.5 has no published cached-input rate, so cached tokens use its listed input rate.

    Confidence: rate-fallback

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.

Claude Sonnet 4.528.4Gemini 3.1 Flash-Lite

Not comparable · BenchAlign v5.6

The coding row is not comparable on the public lane: at least one model is not measured or not ranked there.

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.

1 category rests 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 v5.6 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

Directional only
Claude Sonnet 4.5
26.7
Estimated · #75/105
Gemini 3.1 Flash-Lite
27.5
Estimated · #73/105
Basis
BenchAlign v5.6 lane · 5 vs 2 public rows
Reading
Directional only

Coding

Not comparable
Claude Sonnet 4.5
Not ranked
Gemini 3.1 Flash-Lite
28.4
Estimated · #100/135
Basis
BenchAlign v5.6 lane · 1 vs 3 public rows
Reading
Not comparable

Reasoning

Not comparable
Claude Sonnet 4.5
19.1
Unranked · 1 rankable row
Gemini 3.1 Flash-Lite
Not ranked
Basis
Provisional lane · 1 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
Claude Sonnet 4.5
Not ranked
Gemini 3.1 Flash-Lite
37.4
Unranked · 1 rankable row
Basis
Provisional lane · 0 vs 1 weighted rows
Reading
Not comparable

Knowledge

Not comparable
Claude Sonnet 4.5
Not ranked
Gemini 3.1 Flash-Lite
44.0
Estimated · #73/160
Basis
BenchAlign v5.6 lane · 1 vs 2 public rows
Reading
Not comparable

Multilingual

Not comparable
Claude Sonnet 4.5
Not ranked
Gemini 3.1 Flash-Lite
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
Claude Sonnet 4.5
Not ranked
Gemini 3.1 Flash-Lite
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
Claude Sonnet 4.5
34.6
Unranked · 2 rankable rows
Gemini 3.1 Flash-Lite
Not ranked
Basis
Provisional lane · 2 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 v5.6) 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.

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 Sonnet 4.5
$0.0105
Fits in one request
Gemini 3.1 Flash-Lite
$0.001
Fits in one request

Gemini 3.1 Flash-Lite has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

Claude Sonnet 4.5
$0.195
Fits in one request
Gemini 3.1 Flash-Lite
$0.017
Fits in one request

Gemini 3.1 Flash-Lite 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 Sonnet 4.5
$0.81
Does not fit in one request
Cached input priced at the published list-input rate
Gemini 3.1 Flash-Lite
$0.025
Fits in one request

Claude Sonnet 4.5 does not fit this workload in one request. Claude Sonnet 4.5 has no published cached-input rate, so cached tokens use its listed input rate.

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.

Context window

Maximum documented context; output-token limits may be lower.

Claude Sonnet 4.5

200K

Gemini 3.1 Flash-Lite

Cached-input rate

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

Claude Sonnet 4.5

Not published

Gemini 3.1 Flash-Lite

$0.025 per 1M cached input tokens

Google Gemini API pricing

Documented inputs

Claude Sonnet 4.5

Not sourced

Gemini 3.1 Flash-Lite

Not sourced

Documented outputs

Claude Sonnet 4.5

Not sourced

Gemini 3.1 Flash-Lite

Not sourced

Provider availability

Claude Sonnet 4.5

Not sourced

Gemini 3.1 Flash-Lite

Not sourced

Reasoning profile

Claude Sonnet 4.5

Non-Reasoning

Gemini 3.1 Flash-Lite

Non-Reasoning

Weight access

Claude Sonnet 4.5

Proprietary

Gemini 3.1 Flash-Lite

Proprietary

License

Claude Sonnet 4.5

Proprietary

Gemini 3.1 Flash-Lite

Proprietary

Release date

Claude Sonnet 4.5

2025-09-01

Gemini 3.1 Flash-Lite

2026-03-03

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 Sonnet 4.5 has the higher public score estimate, 47.86 versus 47.46, but the 90% score intervals overlap.
Workload cost
Repository review: $0.195 vs $0.017. Cache-heavy agent loop: $0.81 vs $0.025.
Context tradeoff
Gemini 3.1 Flash-Lite has the larger documented window (1M).
Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, Claude Sonnet 4.5 or Gemini 3.1 Flash-Lite?

Claude Sonnet 4.5 has the higher public score estimate, 47.86 versus 47.46, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.

Which is better for coding, Claude Sonnet 4.5 or Gemini 3.1 Flash-Lite?

Claude Sonnet 4.5 is not ranked on the public lane for coding, so no winner is named for coding.

Which is better for agentic tasks, Claude Sonnet 4.5 or Gemini 3.1 Flash-Lite?

Gemini 3.1 Flash-Lite scores higher for agentic tasks on the public lane, 27.5 to 26.7. Claude Sonnet 4.5 and Gemini 3.1 Flash-Lite are scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which costs less, Claude Sonnet 4.5 or Gemini 3.1 Flash-Lite?

For the stated presets, chat costs $0.0105 on Claude Sonnet 4.5 and $0.001 on Gemini 3.1 Flash-Lite; repository review costs $0.195 and $0.017; the cache-heavy agent loop costs $0.81 and $0.025. Claude Sonnet 4.5 does not fit this workload in one request. Claude Sonnet 4.5 has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, Claude Sonnet 4.5 or Gemini 3.1 Flash-Lite?

Gemini 3.1 Flash-Lite has the larger documented context window: 1M, 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 evidence18 rows

Agentic

  • Terminal-Bench 2.0

    Claude Sonnet 4.550%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • OSWorld-Verified

    Claude Sonnet 4.561.4%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • VITA-Bench

    Claude Sonnet 4.517.0%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • Claude Sonnet 4.548.51%
    Gemini 3.1 Flash-Lite38.46%

    Claude Sonnet 4.5 leads this result

  • JobBench

    Claude Sonnet 4.527.7%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • Terminal-Bench 2.1 (Vals)

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite34.1%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude Sonnet 4.577.2%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • Vibe Code Bench

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite0.00%
    Source

    Not directly comparable

  • LiveCodeBench (Vals)

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite80.1%
    Source

    Not directly comparable

  • SWE-bench (Vals)

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite62.8%
    Source

    Not directly comparable

Reasoning

  • ARC-AGI-2

    Claude Sonnet 4.513.6%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

Multimodal

  • CharXiv

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite73.2%
    Source

    Not directly comparable

Knowledge

  • GPQA

    Claude Sonnet 4.583.4%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • GPQA Diamond (Vals)

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite81.1%
    Source

    Not directly comparable

  • MMLU-Pro (Vals)

    Claude Sonnet 4.5
    Gemini 3.1 Flash-Lite86.2%
    Source

    Not directly comparable

Math

  • AIME 2025

    Claude Sonnet 4.587%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • FrontierMath v2 (Tiers 1-3)

    Claude Sonnet 4.513.495%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

  • FrontierMath v2 (Tier 4)

    Claude Sonnet 4.54.167%
    Source
    Gemini 3.1 Flash-Lite

    Not directly comparable

18 public results · 1 shared

Watch Claude Sonnet 4.5 vs Gemini 3.1 Flash-Lite

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

Read a sample issue

Join 2,000+ readers.

Last updated September 23, 2026