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Gemini 2.5 Flash vs Gemini 4 Argon: pricing and benchmarks

Gemini 2.5 Flash is 85% cheaper on input tokens ($0.30 vs $2.00 per 1M). Gemini 2.5 Flash 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 2.5 Flash costs $195.00 a month versus $1,100 for Gemini 4 Argon, 82% less. Gemini 4 Argon scores 164.6 on the Epoch Capabilities Index vs 140.8 for Gemini 2.5 Flash.

Prices verified October 17, 2026.

Which should you choose?

Overall capability
Gemini 4 Argon

Gemini 4 Argon scores 164.6 on the Epoch Capabilities Index vs 140.8 for Gemini 2.5 Flash.

Price
Gemini 2.5 Flash

Gemini 2.5 Flash costs $0.85 per 1M tokens (3:1 input-to-output mix) vs $4.00 for Gemini 4 Argon, 79% less.

Best value
Too close to call

A trade-off: Gemini 4 Argon is 23.8 ECI points more capable but costs 4.7x as much as Gemini 2.5 Flash.

Pricing and specs

Gemini 2.5 FlashGemini 4 Argon
ProviderGoogleGoogle
API model IDgemini-2.5-flashgemini-4-argon
Input / 1M tokens$0.30$2.00
Cached input / 1M tokens$0.03$0.10
Output / 1M tokens$2.50$10.00
Long-context rates——
Context window1.05M tokens1.05M tokens
Max output66K tokens66K tokens
Batch discount—50% off

Benchmarks

Gemini 2.5 FlashGemini 4 Argon
Epoch Capabilities Index140.8164.6
GPQA Diamond· Science reasoning—96.4%
FrontierMath (Tiers 1–3)· Advanced math—86.0%
SimpleQA Verified· Factual accuracy—76.0%
ARC-AGI-2· Abstract reasoning——
DeepSWE· Coding——
APEX-Agents· Agentic work—82.4%

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

WorkloadGemini 2.5 FlashGemini 4 ArgonDifference
Support chatbot
100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each.
$145.00$700.00Gemini 2.5 Flash 79% cheaper
Document Q&A (RAG)
50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each.
$195.00$1,100Gemini 2.5 Flash 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.
$94.40$468.00Gemini 2.5 Flash 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.

Gemini 2.5 Flash vs Gemini 4 Argon cost calculator

Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.

Gemini 2.5 Flash pricing notes

Google’s previous-generation Flash model.

  • Audio input costs $1.00 per 1M tokens; text, image and video cost $0.30.
  • Output price includes thinking tokens.
Google official pricing ↗

Gemini 4 Argon pricing notes

Google’s flagship reasoning model for complex coding, agents, math and science.

  • Introductory price through November 30, 2026. From December 1, 2026: $4 input, $0.20 cached, $20 output per 1M tokens.
  • Not available on the Gemini API free tier.
  • Output price includes thinking tokens.
  • Max output is 65,536 tokens by default and up to 1,048,576 with long decode.
  • Implicit caching only; explicit context caching is not supported.
  • Priority inference costs 1.8x the standard rate.
Google official pricing ↗

Frequently asked questions

Is Gemini 2.5 Flash cheaper than Gemini 4 Argon?
Gemini 2.5 Flash is 85% cheaper on input tokens ($0.30 vs $2.00 per 1M). Gemini 2.5 Flash 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 2.5 Flash costs $195.00 a month versus $1,100 for Gemini 4 Argon, 82% less.
Which is more capable, Gemini 2.5 Flash or Gemini 4 Argon?
Gemini 4 Argon scores 164.6 on the Epoch Capabilities Index vs 140.8 for Gemini 2.5 Flash.
How much does Gemini 2.5 Flash cost per 1M tokens?
Gemini 2.5 Flash 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.
How much does Gemini 4 Argon cost per 1M tokens?
Gemini 4 Argon costs $2.00 per 1M input tokens and $10.00 per 1M output tokens, and $0.10 per 1M cached input tokens on Google’s standard tier.
Which has the larger context window, Gemini 2.5 Flash or Gemini 4 Argon?
Both offer a 1.05M-token context window.

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