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Comparison · 2 models · Updated Oct 4, 2026

GPT-5 Nano vs Gemini 2.5 Flash-Lite

Too close to call on our weighted score (Gemini 2.5 Flash-Lite 71, GPT-5 Nano 70). The right pick depends on what you value most.

  1. OpenAI

    GPT-5 Nano

    Released Aug 7, 2025

    70/100
    • ECI139.4
    • Price$0.05 / $0.40
    • Context400K
    Full specs Remove GPT-5 Nano

  2. Google

    Gemini 2.5 Flash-Lite

    Released Jun 17, 2025

    71/100
    • ECI133.9
    • Price$0.10 / $0.40
    • Context1.05M
    Full specs Remove Gemini 2.5 Flash-Lite

  3. Add a model

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01 — Verdict

Too close to call

It is close. Our weighted score puts them within 1 points (Gemini 2.5 Flash-Lite 71/100, GPT-5 Nano 70/100), so choose by what matters most for your work: GPT-5 Nano for raw capability and Gemini 2.5 Flash-Lite for long inputs. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGPT-5 NanoCapabilities Index (ECI): GPT-5 Nano 139.4 · Gemini 2.5 Flash-Lite 133.9
  • Lowest priceGPT-5 NanoGPT-5 Nano $0.138 · Gemini 2.5 Flash-Lite $0.175 per 1M tokens (3:1 blend)
  • Longest contextGemini 2.5 Flash-LiteGemini 2.5 Flash-Lite 1,048,576 · GPT-5 Nano 400,000 tokens
  • Widest inputsGemini 2.5 Flash-LiteGPT-5 Nano: Text, Images · Gemini 2.5 Flash-Lite: Text, Images, PDFs, Audio, Video
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5 NanoGemini 2.5 Flash-Lite
CapabilityCapabilities Index (ECI)50%6558
Price25%9186
Inputs & features15%70100
Context window10%4461
Overall100%70/10071/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

GPT-5 Nano vs Gemini 2.5 Flash-Lite specifications side by side
SpecificationGPT-5 NanoOpenAIGemini 2.5 Flash-LiteGoogle
Capability
Capabilities Index (ECI)139.4 (best)133.9
ECI rank#102 of 148 (best)#118 of 148
GPQA DiamondGraduate-level science questions69.4%—
FrontierMath Tiers 1–3Research-level mathematics20.0%—
OTIS Mock AIME 2024–2025Competition mathematics81.1%—
SimpleQA VerifiedShort factual questions11.7%—
Price per million tokens
Input$0.05 (best)$0.10
Output$0.40$0.40
Cached input$0.005 (best)$0.01
Blended (3:1)$0.138 (best)$0.175
Long-context rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial Google API
Limits
Context window400,000 tokens1,048,576 tokens (best)
Max output128,000 tokens (best)65,536 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoYes
VideoNoYes
ReasoningYesminimal · low · medium · highYes
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-5-nanogemini-2.5-flash-lite
API providers21 (best)20
ReleasedAug 7, 2025Jun 17, 2025
Knowledge cutoffMay 30, 2024Jan 2025
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • GPT-5 Nano$1.30
  • Gemini 2.5 Flash-Lite$1.80
04 — Questions

Which should you choose?

Which is better: GPT-5 Nano or Gemini 2.5 Flash-Lite?

It is close. Our weighted score puts them within 1 points (Gemini 2.5 Flash-Lite 71/100, GPT-5 Nano 70/100), so choose by what matters most for your work: GPT-5 Nano for raw capability and Gemini 2.5 Flash-Lite for long inputs. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5 Nano or Gemini 2.5 Flash-Lite?

GPT-5 Nano is cheaper at $0.05 input / $0.40 output per million tokens (official OpenAI API price). Gemini 2.5 Flash-Lite costs $0.10 input / $0.40 output per million tokens (official Google API price). At a typical mix of three input tokens to one output token, that is $0.138 per million tokens for GPT-5 Nano versus $0.175 for Gemini 2.5 Flash-Lite (1.3× as much).

Which scores higher on benchmarks?

GPT-5 Nano scores higher on the Capabilities Index (ECI): GPT-5 Nano 139.4 (#102 of 148) and Gemini 2.5 Flash-Lite 133.9 (#118 of 148). The confidence ranges of the top two overlap (134.9–141.7 vs 129.8–136.3), so treat the gap as small.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5 Nano and Gemini 2.5 Flash-Lite yet, so there is no like-for-like coding score. On overall capability, GPT-5 Nano leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

Gemini 2.5 Flash-Lite has the largest context window at 1,048,576 tokens, against 400,000 for GPT-5 Nano. Maximum output per response: GPT-5 Nano up to 128,000, Gemini 2.5 Flash-Lite up to 65,536 tokens.

Which can read images, PDFs, audio or video?

GPT-5 Nano accepts text and images; Gemini 2.5 Flash-Lite accepts text, images, PDFs, audio and video. Gemini 2.5 Flash-Lite handles the widest range of inputs.

Are any of these open source?

No. GPT-5 Nano and Gemini 2.5 Flash-Lite are proprietary and only available through APIs and apps.

Which is newer?

GPT-5 Nano is the newest, released Aug 7, 2025. Gemini 2.5 Flash-Lite came out Jun 17, 2025. Knowledge cutoff: GPT-5 Nano May 30, 2024, Gemini 2.5 Flash-Lite Jan 2025.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.

05 — Keep comparing

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