Claude Opus 5.5 vs Gemini 2.5 Pro

rates, context and capabilities side by side on the impossibl api, and what the same workload costs on each.

the models at a glance: base rates, context window and modalities
specificationClaude Opus 5.5

anthropic/claude-opus-5-5

Gemini 2.5 Pro

google/gemini-2.5-pro

input · usd / 1m tok$4.00$1.25
output · usd / 1m tok$20.00$10.00
context window1mtokens1mtokens
modalities · in → out

takes text and image in, gives text out

takes text, image, audio and video in, gives text out

pricing

base api rates by model
base api rates · usd per 1m tokensClaude Opus 5.5

anthropic/claude-opus-5-5

Gemini 2.5 Pro

google/gemini-2.5-pro

input$4.00$1.25over 200k · $2.50
output$20.00$10.00over 200k · $15.00
cache read$0.20$0.125over 200k · $0.25
cache write · default ttl$5.00not published
cache write · 1h ttl$8.00not published

brackets are by input tokens per request: a request over a threshold is billed at that bracket's rates for all of its tokens. cache creation can have a separate charge. the estimate below prices one workload at these rates on every model.

specifications

published specifications by model
as publishedClaude Opus 5.5

anthropic/claude-opus-5-5

Gemini 2.5 Pro

google/gemini-2.5-pro

creatorAnthropicGoogle
model typeText generationText generation
context window1,000,000tokens1,000,000tokens
input

takes text and image in, gives text out

takes text, image, audio and video in, gives text out

outputtexttext
tool callingnot verifiednot verified
releasedsep 22, 2026jun 17, 2025
endpoint/v1/chat/completions/v1/chat/completions

unknown means the public catalog does not establish that fact. a model's documented capabilities can differ from what a particular api supports. see the model documentation for integration details.

benchmarks

benchmark scores by model, primary tested configuration
primary configurationClaude Opus 5.5

anthropic/claude-opus-5-5

no benchmarks yet

Gemini 2.5 Pro

google/gemini-2.5-pro

intelligence index · gateway ranknot measured16.7#62 of 90
coding indexnot measured33.3#49 of 60
agentic indexnot measured3.5#46 of 49
omnisciencenot measured-16.4#58 of 86
gpqanot measured84.4%#52 of 88
humanity’s last examnot measured22.5%#57 of 89
terminal-bench v2.1not measured28.5%#48 of 57
aime 2025not measured87.7%
livecodebenchnot measured80.1%
mmmu-pronot measured74.9%
aa-lcrnot measured69.0%
tau2not measured54.1%
ifbenchnot measured48.7%
scicodenot measured46.3%
terminal-bench hardnot measured26.5%
gdp.pdf all-passnot measured10.2%
tau bankingnot measured9.7%
critptnot measured2.6%
automationbench partialnot measured2.2%
terminal-bench v4.0not measured0.0%

Gemini 2.5 Pro source ↗

each column describes the tested configuration named under the model; performance and costs can differ on impossibl. a score one model was not measured on is left blank rather than scored zero. indices are ranked against every model on the gateway with one. last checked 2026-09-11.

estimate your cost

one token workload, priced on every model at the published rates, in usd. change the numbers to match yours.

token workload

total input, including cached tokens

include billable reasoning tokens

the same token usage in each request

a subset of total input, never additional tokens

Claude Opus 5.5

anthropic/claude-opus-5-5

estimated usage cost

$14.00

1,000 requests × (1,000 uncached input × $4.00 + 500 output × $20.00) / 1,000,000 = $14.00

base rates; no context pricing tiers are published.

Gemini 2.5 Pro

google/gemini-2.5-pro

estimated usage cost

$6.25

1,000 requests × (1,000 uncached input × $1.25 + 500 output × $10.00) / 1,000,000 = $6.25

base rates: up to 200,000 input tokens per request, inclusive.

estimates use published impossibl api usage rates. configured billing adjustments, funding fees, taxes, and custom workspace rates are excluded and may change the final amount.

image and audio usage, cache creation, and additional tool charges are excluded. reasoning tokens count as billable output, even when they are not visible in the response.

summary

Claude Opus 5.5 and Gemini 2.5 Pro are available through the Impossibl API. they share the /v1/chat/completions endpoint; the model identifier selects the model for a request.

Claude Opus 5.5 is created by Anthropic. It has a 1,000,000-token context window. Base API pricing (USD): $4.00 per million input tokens; $20.00 per million output tokens.

Gemini 2.5 Pro is created by Google. It has a 1,000,000-token context window. Base API pricing (USD): $1.25 per million input tokens; $10.00 per million output tokens. Above 200,000 input tokens per request, context-tier rates apply to the whole request.

Claude Opus 5.5Gemini 2.5 Pro

this page compares Claude Opus 5.5 vs Gemini 2.5 Pro as listed by the impossibl public api. prices and availability come from that catalog, refreshed here every five minutes. this is an impossibl offering, not a comparison of independent hosting-provider quotes.

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