Claude Sonnet 5.5 vs Gemini 3.5 Flash-Lite: pricing and benchmarks
Gemini 3.5 Flash-Lite is 85% cheaper on input tokens ($0.30 vs $2.00 per 1M). Gemini 3.5 Flash-Lite is 75% cheaper on output tokens ($2.50 vs $10.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.5 Flash-Lite costs $195.00 a month versus $1,100 for Claude Sonnet 5.5, 82% less. Claude Sonnet 5.5 scores 164.4 on the Epoch Capabilities Index vs 145.2 for Gemini 3.5 Flash-Lite.
Which should you choose?
Claude Sonnet 5.5 scores 164.4 on the Epoch Capabilities Index vs 145.2 for Gemini 3.5 Flash-Lite.
Claude Sonnet 5.5 scores 88.8% on FrontierMath (Tiers 1–3) vs 26.0% for Gemini 3.5 Flash-Lite.
Gemini 3.5 Flash-Lite costs $0.85 per 1M tokens (3:1 input-to-output mix) vs $4.00 for Claude Sonnet 5.5, 79% less.
A trade-off: Claude Sonnet 5.5 is 19.3 ECI points more capable but costs 4.7x as much as Gemini 3.5 Flash-Lite.
Pricing and specs
| Claude Sonnet 5.5 | Gemini 3.5 Flash-Lite | |
|---|---|---|
| Provider | Anthropic | |
| API model ID | claude-sonnet-5-5 | gemini-3.5-flash-lite |
| Input / 1M tokens | $2.00 | $0.30 |
| Cached input / 1M tokens | $0.20 | $0.03 |
| Output / 1M tokens | $10.00 | $2.50 |
| Long-context rates | — | — |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 66K tokens |
| Batch discount | 50% off | 50% off |
Benchmarks
| Claude Sonnet 5.5 | Gemini 3.5 Flash-Lite | |
|---|---|---|
| Epoch Capabilities Index | 164.4 | 145.2 |
| GPQA Diamond· Science reasoning | 95.6% | 83.3% |
| FrontierMath (Tiers 1–3)· Advanced math | 88.8% | 26.0% |
| SimpleQA Verified· Factual accuracy | 46.5% | — |
| ARC-AGI-2· Abstract reasoning | — | 10.3% |
| DeepSWE· Coding | — | — |
| APEX-Agents· Agentic work | 75.5% | 29.3% |
Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks
Monthly cost for real workloads
| Workload | Claude Sonnet 5.5 | Gemini 3.5 Flash-Lite | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $700.00 | $145.00 | Gemini 3.5 Flash-Lite 79% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $1,100 | $195.00 | Gemini 3.5 Flash-Lite 82% cheaper |
Coding agent 10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens. | $496.00 | $94.40 | Gemini 3.5 Flash-Lite 81% cheaper |
Cached chatbot The same 100,000-reply support chatbot, but 60% of each prompt (system prompt + conversation history) is served from the prompt cache. | $538.00 | $120.70 | Gemini 3.5 Flash-Lite 78% cheaper |
Meeting notes 10,000 meetings a month summarized from ~12,000-token transcripts, ~1,000 output tokens each. | $340.00 | $61.00 | Gemini 3.5 Flash-Lite 82% cheaper |
Bulk translation 200,000 short translations a month, ~800 input and ~800 output tokens each. | $1,920 | $448.00 | Gemini 3.5 Flash-Lite 77% cheaper |
Content moderation 1,000,000 classifications a month, ~400 input tokens and ~80 output tokens each. | $1,600 | $320.00 | Gemini 3.5 Flash-Lite 80% cheaper |
Article drafting 300 long-form articles a month written from a ~4,000-token brief and outline, ~5,000 output tokens each. | $17.40 | $4.11 | Gemini 3.5 Flash-Lite 76% cheaper |
Code review bot 30,000 pull-request reviews a month, ~5,000 input tokens each (30% cached repository context) and ~700 output tokens. | $429.00 | $85.35 | Gemini 3.5 Flash-Lite 80% cheaper |
Invoice extraction 100,000 documents a month parsed into structured JSON, ~1,200 input and ~250 output tokens each. | $490.00 | $98.50 | Gemini 3.5 Flash-Lite 80% cheaper |
Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.
Claude Sonnet 5.5 vs Gemini 3.5 Flash-Lite cost calculator
- $195.00/mo$0.0039 / req
- Claude Sonnet 5.5Anthropic$1,100/mo$0.02 / req
Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.
Claude Sonnet 5.5 pricing notes
Anthropic’s fast mid-tier model, successor to Claude Sonnet 5 at the same price.
- Cache writes cost $2.50 (5-minute cache) or $4 (1-hour cache) per 1M tokens.
- US-only inference (inference_geo: "us") costs 1.1x.
Gemini 3.5 Flash-Lite pricing notes
Google’s lowest-cost Gemini 3.5 model for high-volume work.
- The same input price applies to text, image, video and audio.
- Output price includes thinking tokens.
Frequently asked questions
- Is Claude Sonnet 5.5 cheaper than Gemini 3.5 Flash-Lite?
- Gemini 3.5 Flash-Lite is 85% cheaper on input tokens ($0.30 vs $2.00 per 1M). Gemini 3.5 Flash-Lite is 75% cheaper on output tokens ($2.50 vs $10.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.5 Flash-Lite costs $195.00 a month versus $1,100 for Claude Sonnet 5.5, 82% less.
- Which is more capable, Claude Sonnet 5.5 or Gemini 3.5 Flash-Lite?
- Claude Sonnet 5.5 scores 164.4 on the Epoch Capabilities Index vs 145.2 for Gemini 3.5 Flash-Lite.
- How much does Claude Sonnet 5.5 cost per 1M tokens?
- Claude Sonnet 5.5 costs $2.00 per 1M input tokens and $10.00 per 1M output tokens, and $0.20 per 1M cached input tokens on Anthropic’s standard tier.
- How much does Gemini 3.5 Flash-Lite cost per 1M tokens?
- Gemini 3.5 Flash-Lite costs $0.30 per 1M input tokens and $2.50 per 1M output tokens, and $0.03 per 1M cached input tokens on Google’s standard tier.
- Which has the larger context window, Claude Sonnet 5.5 or Gemini 3.5 Flash-Lite?
- Gemini 3.5 Flash-Lite has the larger context window: 1.05M tokens versus 1M for Claude Sonnet 5.5.