Coding
Like-for-like- Claude Fable 5.1
- 81.2
- Gemini 3.5 Flash-Lite
- 54.2
- Weighted basis
- 1 vs 1 rows
- Reading
- Claude Fable 5.1 leads
Claude Fable 5.1 vs Gemini 3.5 Flash-Lite
Updated September 1, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
Claude Fable 5.1 has the higher public score estimate, 82.74 versus 65.04, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.
1 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.
Coding work
Code generation, repair, and software-engineering tasks
Claude Fable 5.1
Claude Fable 5.1 leads on the same 1 weighted benchmark row.
Confidence: limited
Chat turn cost
1K fresh input + 500 output tokens
Gemini 3.5 Flash-Lite
Gemini 3.5 Flash-Lite has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Gemini 3.5 Flash-Lite
Gemini 3.5 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 3.5 Flash-Lite
Gemini 3.5 Flash-Lite has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
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
Long documents
Prompts that approach the documented context limit
No clear pick
The documented context windows are equal.
Confidence: documented
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
17 Claude Fable 5.1 only
1 Shared
4 Gemini 3.5 Flash-Lite only
- Shared results
- 1
- Claude Fable 5.1 only
- 17
- Gemini 3.5 Flash-Lite only
- 4
- Like-for-like categories
- 1 / 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- Claude Fable 5.1
- Not measured
- Gemini 3.5 Flash-Lite
- 63.4
- Weighted basis
- 0 vs 2 rows
- Reading
- Not comparable
Reasoning
Not comparable- Claude Fable 5.1
- 90.0
- Gemini 3.5 Flash-Lite
- 72.2
- Weighted basis
- 1 vs 1 rows
- Reading
- Not comparable
Knowledge
Not comparable- Claude Fable 5.1
- 65.0
- Gemini 3.5 Flash-Lite
- Not measured
- Weighted basis
- 1 vs 0 rows
- Reading
- Not comparable
Math
Not comparable- Claude Fable 5.1
- Not measured
- Gemini 3.5 Flash-Lite
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Multilingual
Not comparable- Claude Fable 5.1
- Not measured
- Gemini 3.5 Flash-Lite
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Multimodal
Not comparable- Claude Fable 5.1
- Not measured
- Gemini 3.5 Flash-Lite
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Instruction following
Not comparable- Claude Fable 5.1
- Not measured
- Gemini 3.5 Flash-Lite
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
| Category | Claude Fable 5.1 | Gemini 3.5 Flash-Lite | Weighted basis | Reading |
|---|---|---|---|---|
| Coding | 81.2 | 54.2 | Like-for-like1 vs 1 rows | Claude Fable 5.1 leads |
| Agentic | Not measured | 63.4 | Not comparable0 vs 2 rows | Not comparable |
| Reasoning | 90.0 | 72.2 | Not comparable1 vs 1 rows | Not comparable |
| Knowledge | 65.0 | Not measured | Not comparable1 vs 0 rows | Not comparable |
| Math | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Multilingual | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Multimodal | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Instruction following | Not measured | Not measured | Not comparable0 vs 0 rows | 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.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
SWE-bench Pro
Coding
Claude Fable 5.1: 81.2%Gemini 3.5 Flash-Lite: 54.2%Normalized gap 27.0Claude Fable 5.1 source Gemini 3.5 Flash-Lite source
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 Fable 5.1
- $0.035
- Fits in one request
- Gemini 3.5 Flash-Lite
- $0.00155
- Fits in one request
Gemini 3.5 Flash-Lite has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Claude Fable 5.1
- $0.65
- Fits in one request
- Gemini 3.5 Flash-Lite
- $0.0225
- Fits in one request
Gemini 3.5 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 Fable 5.1
- $0.75
- Fits in one request
- Gemini 3.5 Flash-Lite
- $0.037
- Fits in one request
Gemini 3.5 Flash-Lite has the lower modeled cost
Costs use the listed standard API rates.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationClaude Fable 5.1Gemini 3.5 Flash-Lite
Context window
Maximum documented context; output-token limits may be lower.
Claude Fable 5.1
Gemini 3.5 Flash-Lite
API model ID
Claude Fable 5.1
claude-fable-5-1
Anthropic Fable 5.1 and Mythos 5.1 launchGemini 3.5 Flash-Lite
gemini-3.5-flash-lite
Google Gemini 3.5 Flash-Lite model documentationCached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Claude Fable 5.1
$0.25 per 1M cached input tokens
Anthropic Fable 5.1 launchGemini 3.5 Flash-Lite
$0.03 per 1M cached input tokens
Google Gemini API pricingDocumented inputs
Claude Fable 5.1
Not sourced
Gemini 3.5 Flash-Lite
text, image, video, audio, pdf
Google Gemini 3.5 Flash-Lite model documentationDocumented outputs
Claude Fable 5.1
Not sourced
Gemini 3.5 Flash-Lite
Provider availability
Claude Fable 5.1
Generally Available · Claude API, Claude products, AWS, Google Cloud, Microsoft Azure
Anthropic Fable 5.1 and Mythos 5.1 launchGemini 3.5 Flash-Lite
Generally Available · Gemini API, Google AI Studio
Google latest Gemini model guideReasoning profile
Claude Fable 5.1
Reasoning
Gemini 3.5 Flash-Lite
Reasoning
Weight access
Claude Fable 5.1
Proprietary
Gemini 3.5 Flash-Lite
Proprietary
License
Claude Fable 5.1
Proprietary
Gemini 3.5 Flash-Lite
Proprietary
Release date
Claude Fable 5.1
2026-09-01
Gemini 3.5 Flash-Lite
2026-07-21
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 Fable 5.1 has the higher public score estimate, 82.74 versus 65.04, but the 90% score intervals overlap.
- Workload cost
- Repository review: $0.65 vs $0.0225. Cache-heavy agent loop: $0.75 vs $0.037.
- Context tradeoff
- Both models list 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 evidence22 rows
Agentic
Terminal-Bench 4.0
Claude Fable 5.155.80%SourceGemini 3.5 Flash-Lite—Not directly comparable
Terminal-Bench-Science 0.1
Claude Fable 5.152.6%SourceGemini 3.5 Flash-Lite—Not directly comparable
OSWorld 2.0
Claude Fable 5.141.7%SourceGemini 3.5 Flash-Lite—Not directly comparable
AutomationBench
Claude Fable 5.131.4%SourceGemini 3.5 Flash-Lite—Not directly comparable
Toolathlon-Verified
Claude Fable 5.177.8%SourceGemini 3.5 Flash-Lite—Not directly comparable
Toolathlon Verified Pass@3
Claude Fable 5.181.5%SourceGemini 3.5 Flash-Lite—Not directly comparable
Toolathlon Verified Pass³
Claude Fable 5.173.1%SourceGemini 3.5 Flash-Lite—Not directly comparable
Toolathlon Verified avg. turns
Claude Fable 5.123.7 turnsSourceGemini 3.5 Flash-Lite—Not directly comparable
Terminal-Bench 2.0
Claude Fable 5.1—Gemini 3.5 Flash-Lite54%SourceNot directly comparable
OSWorld-Verified
Claude Fable 5.1—Gemini 3.5 Flash-Lite74%SourceNot directly comparable
Coding
SWE-bench Pro
Claude Fable 5.181.2%SourceGemini 3.5 Flash-Lite54.2%SourceClaude Fable 5.1 leads this result
SWE Multilingual
Claude Fable 5.189.1%SourceGemini 3.5 Flash-Lite—Not directly comparable
SWE Multimodal
Claude Fable 5.154.7%SourceGemini 3.5 Flash-Lite—Not directly comparable
deepSwe
Claude Fable 5.167.4%SourceGemini 3.5 Flash-Lite—Not directly comparable
ProgramBench
Claude Fable 5.187.6%SourceGemini 3.5 Flash-Lite—Not directly comparable
cursorBench32
Claude Fable 5.173.4%SourceGemini 3.5 Flash-Lite—Not directly comparable
Terminal-Bench 2.0
Claude Fable 5.1—Gemini 3.5 Flash-Lite54.0%SourceNot directly comparable
Reasoning
Knowledge
Frequently asked questions
Which is better, Claude Fable 5.1 or Gemini 3.5 Flash-Lite?
Claude Fable 5.1 has the higher public score estimate, 82.74 versus 65.04, 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 Fable 5.1 or Gemini 3.5 Flash-Lite?
Claude Fable 5.1 leads the like-for-like coding comparison across 1 shared weighted benchmark row.
Which is better for agentic tasks, Claude Fable 5.1 or Gemini 3.5 Flash-Lite?
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, Claude Fable 5.1 or Gemini 3.5 Flash-Lite?
For the stated presets, chat costs $0.035 on Claude Fable 5.1 and $0.00155 on Gemini 3.5 Flash-Lite; repository review costs $0.65 and $0.0225; the cache-heavy agent loop costs $0.75 and $0.037. Costs use the listed standard API rates.
Which has the larger context window, Claude Fable 5.1 or Gemini 3.5 Flash-Lite?
Both models list the same context window, 1M.
Related comparisons
Last updated September 1, 2026
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