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Model vs model

Claude Opus 5.5 vs Kimi K3

Claude Opus 5.5 and Kimi K3 are both in llmwise. What each gets on every plan, what it reads, how it's served and what happens when its provider fails, from the catalog and the code that runs them.

Model prices and specs checked against OpenRouter's Claude Opus 5.5 page, OpenRouter's Kimi K3 page. Updated .

Short answer

Kimi K3 gets twice as many messages: up to 125 messages a month on Pro, against up to 62 messages a month for Claude Opus 5.5. Otherwise, only Claude Opus 5.5 reads a PDF as the whole file, only Claude Opus 5.5 can be passed to another model by its maker's safety system, and only Kimi K3 is in the free trial. In our test runs, Claude Opus 5.5 passed 49 of the 50 prompts both answered and Kimi K3 46; 5 prompts split them, most on summarization (5 to 3).

Claude Opus 5.5 vs Kimi K3, prompt by prompt

Every prompt Claude Opus 5.5 and Kimi K3 both answered, compared directly, their biggest differences first. One run each, through OpenRouter: a wait depends on the provider and the load that day, so a lead under 10% counts as close.

Of the 50 prompts both answered, both passed 45, only Claude Opus 5.5 passed 4, only Kimi K3 passed 1, and neither passed 0. Claude Opus 5.5 answered sooner on 11 of the 50 and Kimi K3 on 33; the rest were within 10% of each other. The 50 replies cost $0.5360 on Claude Opus 5.5 and $0.1938 on Kimi K3: 2.8× less on Kimi K3.

The 5 prompts only one of Claude Opus 5.5 and Kimi K3 passed

  • A product announcement with five rules (writing): Claude Opus 5.5 passed and Kimi K3 didn't. Claude Opus 5.5: Graded 4.7 of 5 on average (lowest 4). Kimi K3: Graded 4.3 of 5 on average (lowest 4); but doesn't end with a question.

  • Argue both sides of free buses (writing): Kimi K3 passed and Claude Opus 5.5 didn't. Claude Opus 5.5: Graded 4.7 of 5 on average (lowest 4); but a paragraph of 93 words, over the 90 allowed. Kimi K3: Graded 4.7 of 5 on average (lowest 4).

  • An article in three bullets (summarization): Claude Opus 5.5 passed and Kimi K3 didn't. Claude Opus 5.5: Graded 5.0 of 5 on average (lowest 5). Kimi K3: Graded 4.0 of 5 on average (lowest 3); but 62 words, over the 60 allowed.

  • An email thread in one sentence (summarization): Claude Opus 5.5 passed and Kimi K3 didn't. Claude Opus 5.5: Graded 5.0 of 5 on average (lowest 5). Kimi K3: Graded 5.0 of 5 on average (lowest 5); but 32 words, over the 30 allowed.

  • A refund request outside the window (customer support): Claude Opus 5.5 passed and Kimi K3 didn't. Claude Opus 5.5: Graded 5.0 of 5 on average (lowest 5). Kimi K3: Graded 4.0 of 5 on average (lowest 2).

Job by job, the widest gaps first

  • Summarization: Claude Opus 5.5 passed 5 of 5 and Kimi K3 3 of 5. Their median waits were close, 3.7 s against 3.4 s. Kimi K3 cost 2.8× less, $0.0475 against $0.0172 for the 5 replies. Claude Opus 5.5's replies ran 53% longer, in tokens of reply, thinking not counted.

  • Customer support: Claude Opus 5.5 passed 5 of 5 and Kimi K3 4 of 5. Kimi K3 answered 1.5× sooner at the median, 6.4 s against 4.3 s. Kimi K3 cost 2.4× less, $0.0540 against $0.0228 for the 5 replies. Claude Opus 5.5's replies ran 45% longer, in tokens of reply, thinking not counted.

  • RAG and answering from documents: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Their median waits were close, 2.9 s against 2.6 s. Kimi K3 cost 5.0× less, $0.0367 against $0.0073 for the 5 replies. Claude Opus 5.5's replies ran 88% longer, in tokens of reply, thinking not counted.

  • Writing: Claude Opus 5.5 passed 4 of 5 and Kimi K3 4 of 5. Kimi K3 answered 2.8× sooner at the median, 8.2 s against 3.0 s. Kimi K3 cost 4.8× less, $0.0923 against $0.0192 for the 5 replies. Claude Opus 5.5's replies ran 47% longer, in tokens of reply, thinking not counted.

  • SQL: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Kimi K3 answered 2.7× sooner at the median, 4.3 s against 1.6 s. Kimi K3 cost 3.9× less, $0.0459 against $0.0118 for the 5 replies. Claude Opus 5.5's replies ran 131% longer, in tokens of reply, thinking not counted.

  • Translation: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Their median waits were close, 5.5 s against 5.2 s. Kimi K3 cost 3.0× less, $0.0540 against $0.0179 for the 5 replies. Their replies ran to about the same length.

  • Coding: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Kimi K3 answered 1.7× sooner at the median, 7.2 s against 4.1 s. Kimi K3 cost 2.7× less, $0.0853 against $0.0316 for the 5 replies. Claude Opus 5.5's replies ran 42% longer, in tokens of reply, thinking not counted.

  • Data analysis: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Kimi K3 answered 1.3× sooner at the median, 4.6 s against 3.5 s. Kimi K3 cost 1.9× less, $0.0654 against $0.0339 for the 5 replies. Claude Opus 5.5's replies ran 25% longer, in tokens of reply, thinking not counted.

  • Agents and tool use: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Kimi K3 answered 1.6× sooner at the median, 3.1 s against 2.0 s. Kimi K3 cost 1.9× less, $0.0252 against $0.0135 for the 5 replies. Claude Opus 5.5's replies ran 19% longer, in tokens of reply, thinking not counted.

  • Math: Claude Opus 5.5 passed 5 of 5 and Kimi K3 5 of 5. Claude Opus 5.5 answered 1.4× sooner at the median, 3.9 s against 5.4 s. Kimi K3 cost 1.6× less, $0.0298 against $0.0187 for the 5 replies. Claude Opus 5.5's replies ran 74% longer, in tokens of reply, thinking not counted.

All 50 prompts: who passed, who answered sooner, who cost less
Claude Opus 5.5 and Kimi K3 on each prompt of our test runs
PromptResultSoonerCheaper
Turn a title into a URL slugBoth passedKimi K3, 1.2×took 3.1 s and 2.6 sKimi K3, 1.6×cost $0.0055 and $0.0035
Parse a duration like “1h 30m”Both passedClosetook 7.2 s and 7.1 sKimi K3, 1.8×cost $0.0112 and $0.0063
Merge overlapping intervalsBoth passedKimi K3, 1.8×took 3.7 s and 2.0 sKimi K3, 2.1×cost $0.0077 and $0.0036
Evaluate an arithmetic expression, no evalBoth passedKimi K3, 1.6×took 15.8 s and 9.9 sKimi K3, 3.0×cost $0.0336 and $0.0113
Parse CSV with quoted fieldsBoth passedKimi K3, 2.9×took 11.9 s and 4.1 sKimi K3, 3.9×cost $0.0273 and $0.0069
Announce a second bakery shop on LinkedInBoth passedKimi K3, 2.2×took 8.7 s and 3.9 sKimi K3, 3.8×cost $0.0175 and $0.0046
Rewrite corporate jargon in plain wordsBoth passedKimi K3, 2.5×took 5.1 s and 2.0 sKimi K3, 2.6×cost $0.0078 and $0.0030
Decline a meeting and offer two timesBoth passedKimi K3, 1.4×took 4.1 s and 3.0 sKimi K3, 1.7×cost $0.0056 and $0.0034
A product announcement with five rulesOnly Claude Opus 5.5Kimi K3, 3.6×took 8.2 s and 2.3 sKimi K3, 5.2×cost $0.0170 and $0.0033
Argue both sides of free busesOnly Kimi K3Kimi K3, 6.3×took 22.5 s and 3.6 sKimi K3, 9.1×cost $0.0443 and $0.0049
A discount, then sales taxBoth passedClaude Opus 5.5, 1.8×took 2.7 s and 5.0 sClosecost $0.0037 and $0.0037
Pens at 3 for $4Both passedClosetook 5.3 s and 5.4 sKimi K3, 1.8×cost $0.0084 and $0.0046
Compound interest over three yearsBoth passedClaude Opus 5.5, 1.6×took 3.7 s and 5.9 sClosecost $0.0043 and $0.0044
Four-digit numbers whose digits sum to 9Both passedClaude Opus 5.5, 1.3×took 4.7 s and 6.0 sKimi K3, 2.4×cost $0.0077 and $0.0032
The highest of three dice is a 5Both passedKimi K3, 1.6×took 3.9 s and 2.4 sKimi K3, 2.1×cost $0.0057 and $0.0027
An article in three bulletsOnly Claude Opus 5.5Kimi K3, 2.9×took 8.1 s and 2.8 sKimi K3, 6.1×cost $0.0171 and $0.0028
An email thread in one sentenceOnly Claude Opus 5.5Claude Opus 5.5, 2.4×took 2.6 s and 6.4 sKimi K3, 1.5×cost $0.0044 and $0.0030
Decisions and action items from a meetingBoth passedKimi K3, 1.7×took 5.8 s and 3.4 sKimi K3, 2.7×cost $0.0118 and $0.0044
A quarterly memo for the CEOBoth passedClaude Opus 5.5, 4.4×took 3.5 s and 15.7 sKimi K3, 1.5×cost $0.0075 and $0.0049
A study with a negative resultBoth passedKimi K3, 1.1×took 3.7 s and 3.2 sKimi K3, 3.1×cost $0.0066 and $0.0021
The region with the most revenueBoth passedKimi K3, 1.9×took 4.1 s and 2.2 sKimi K3, 1.8×cost $0.0087 and $0.0049
Average order value in AugustBoth passedKimi K3, 1.7×took 4.4 s and 2.7 sKimi K3, 2.0×cost $0.0107 and $0.0054
Revenue change from July to AugustBoth passedClaude Opus 5.5, 1.3×took 5.1 s and 6.4 sKimi K3, 1.9×cost $0.0120 and $0.0064
A median, filtered two waysBoth passedKimi K3, 1.3×took 4.6 s and 3.5 sKimi K3, 1.9×cost $0.0079 and $0.0042
Correlation between ad spend and sign-upsBoth passedClaude Opus 5.5, 1.8×took 11.5 s and 20.2 sKimi K3, 2.0×cost $0.0261 and $0.0131
A late orderBoth passedKimi K3, 3.1×took 7.8 s and 2.5 sKimi K3, 2.5×cost $0.0114 and $0.0045
A return inside the windowBoth passedClosetook 4.4 s and 4.3 sKimi K3, 2.2×cost $0.0074 and $0.0033
A frustrated customerBoth passedKimi K3, 1.1×took 6.4 s and 5.6 sKimi K3, 1.8×cost $0.0111 and $0.0063
A refund request outside the windowOnly Claude Opus 5.5Kimi K3, 2.3×took 6.1 s and 2.6 sKimi K3, 2.4×cost $0.0106 and $0.0045
A message with a planted instructionBoth passedClaude Opus 5.5, 1.5×took 7.9 s and 11.5 sKimi K3, 3.3×cost $0.0136 and $0.0041
A delivery message into SpanishBoth passedKimi K3, 1.1×took 3.2 s and 2.9 sKimi K3, 2.1×cost $0.0064 and $0.0031
A product description into FrenchBoth passedClosetook 5.8 s and 5.4 sKimi K3, 3.1×cost $0.0113 and $0.0037
A meeting note into GermanBoth passedKimi K3, 1.9×took 5.5 s and 3.0 sKimi K3, 6.9×cost $0.0096 and $0.0014
Idioms into natural JapaneseBoth passedClaude Opus 5.5, 1.4×took 3.6 s and 5.2 sKimi K3, 1.2×cost $0.0062 and $0.0053
A lease clause into Brazilian PortugueseBoth passedKimi K3, 1.1×took 11.4 s and 10.1 sKimi K3, 4.7×cost $0.0204 and $0.0044
Customers in one countryBoth passedKimi K3, 2.3×took 2.5 s and 1.1 sKimi K3, 2.7×cost $0.0048 and $0.0018
Count orders by statusBoth passedKimi K3, 1.6×took 2.5 s and 1.5 sKimi K3, 5.7×cost $0.0049 and $0.0009
Revenue by categoryBoth passedKimi K3, 2.7×took 4.3 s and 1.6 sKimi K3, 4.9×cost $0.0092 and $0.0019
Every customer, even those without ordersBoth passedKimi K3, 2.0×took 5.0 s and 2.5 sKimi K3, 3.1×cost $0.0094 and $0.0031
Monthly revenue with a running totalBoth passedKimi K3, 3.1×took 7.8 s and 2.5 sKimi K3, 4.2×cost $0.0176 and $0.0042
A fact from one sectionBoth passedClaude Opus 5.5, 2.6×took 2.5 s and 6.5 sKimi K3, 5.4×cost $0.0054 and $0.0010
Core hours and start timesBoth passedKimi K3, 2.1×took 2.6 s and 1.2 sKimi K3, 4.9×cost $0.0054 and $0.0011
Two sections in one answerBoth passedClosetook 2.9 s and 2.6 sKimi K3, 2.7×cost $0.0053 and $0.0020
A later amendment changes the answerBoth passedKimi K3, 1.6×took 7.7 s and 4.8 sKimi K3, 6.8×cost $0.0148 and $0.0022
A question the handbook doesn't answerBoth passedKimi K3, 3.6×took 3.4 s and 0.9 sKimi K3, 5.7×cost $0.0057 and $0.0010
Pick the tool and work out the dateBoth passedClaude Opus 5.5, 1.4×took 2.7 s and 3.7 sKimi K3, 1.3×cost $0.0041 and $0.0032
Convert a currencyBoth passedClosetook 2.8 s and 2.9 sKimi K3, 1.6×cost $0.0041 and $0.0025
Book a meeting from a sentenceBoth passedKimi K3, 4.6×took 7.2 s and 1.6 sKimi K3, 1.9×cost $0.0059 and $0.0031
Search, but don't bookBoth passedKimi K3, 1.6×took 3.1 s and 2.0 sKimi K3, 1.4×cost $0.0046 and $0.0034
Two calls with a unit conversionBoth passedKimi K3, 2.0×took 3.4 s and 1.7 sKimi K3, 5.2×cost $0.0064 and $0.0012

Claude Opus 5.5 vs Kimi K3 in our test runs

Claude Opus 5.5 and Kimi K3 on the same prompts, job by job: how many replies passed their check.

Based on 100 of our test runs on , through OpenRouter with the app's own prompt and settings. Updated .

Claude Opus 5.5 and Kimi K3 in our test runs, job by job
JobClaude Opus 5.5Kimi K3
Coding5 of 55 of 5
Writing4 of 54 of 5
Math5 of 55 of 5
Summarization5 of 53 of 5
Data analysis5 of 55 of 5
Customer support5 of 54 of 5
Translation5 of 55 of 5
SQL5 of 55 of 5
RAG and answering from documents5 of 55 of 5
Agents and tool use5 of 55 of 5
All jobs49 of 50 · 1 message each · $0.0107 a reply46 of 50 · 1 message each · $0.0039 a reply

The same prompts, sent to both through llmwise's own pipeline and checked the same way: five for each job. A bold count is the one that passed more. Messages: what each reply counted as on Pro. Cost: what OpenRouter charged us per reply, on average. Every prompt, and how it's scored.

Where they differed most, summarization: both replies to a prompt only one of them passed.

An everyday prompt: “An article in three bullets”, in full.

  • Claude Opus 5.5

    Passed: Graded 5.0 of 5 on average (lowest 5).

    - Aldmoor's six-month Market Street protected bike lane trial ended; council votes in November on keeping them.
    - Daily bike trips rose from 900 to 2,300, car traffic fell 14%, rush-hour drive times rose about a minute, and cyclist injuries dropped from nine to two.
    - Businesses were split; permanence would cost €1.1 million beyond the €410,000 installation.

    727 tokens in, 674 out (539 of them reasoning) · 8.1 s · $0.0171 · 1 message on Pro · answered by anthropic/claude-opus-5.5 via Claude Platform on AWS ·

  • Kimi K3

    Failed: Graded 4.0 of 5 on average (lowest 3); but 62 words, over the 60 allowed.

    - Aldmoor's six-month protected bike lane trial on Market Street ended; the council votes in November on making them permanent.
    - Bike trips rose from 900 to 2,300 daily, cyclist injuries dropped from nine to two, while car traffic fell 14% with only slightly longer rush-hour drive times.
    - Businesses were split on customer impact; installation cost €410,000, with permanent lanes requiring €1.1 million more.

    608 tokens in, 109 out (10 of them reasoning) · 2.8 s · $0.0028 · 1 message on Pro · answered by moonshotai/kimi-k3 via Phala ·

Claude Opus 5.5 and Kimi K3 on every plan

Whether the one-time free trial reaches each model, then each paid plan's messages on it.

Messages on Claude Opus 5.5 and Kimi K3, plan by plan
PlanPriceClaude Opus 5.5Kimi K3
Free$0Not in the trialIn the one-time trial of 5 messages
Pro$20 a monthUp to 62 a monthUp to 125 a month
Max$50 a monthUp to 200 a monthUp to 400 a month
Ultra$100 a monthUp to 450 a monthUp to 900 a month
Studio$200 a monthUp to 1,000 a monthUp to 2,000 a month

Prices don't include tax, which is added where it applies and shown before you pay. A paid plan's month is one allowance shared by every model, so each monthly count is the most you get if all of it goes to that model. It renews each billing period; everyday models refill daily at 00:00 UTC. Long chats count more per reply. How pricing works.

Every limit is published. Paid plans also have a monthly fair-use limit on AI cost: Pro $7.50, Max $20, Ultra $42, Studio $85. Using every message on your plan at typical sizes stays under it; very large messages and heavy research use it faster. Every limit, explained.

What differs

  • Messages on Pro

    Kimi K3 gets twice as many messages: up to 125 messages a month on Pro, against up to 62 messages a month for Claude Opus 5.5.

  • Context window

    Claude Opus 5.5 takes up to 1M tokens; Kimi K3 up to 1.05M tokens. A chat in llmwise holds up to 200k tokens, which fits in either, so the difference shows only through each maker's own API.

  • Images and PDFs

    Both read images. Kimi K3 gets a PDF's text rather than the file itself.

  • On Free

    Kimi K3 is in the free trial; Claude Opus 5.5 needs a paid plan.

  • Where messages go

    Claude Opus 5.5: Sent to Anthropic directly. Kimi K3: Served through OpenRouter, only by hosts that don't store or train on prompts. The maker's own endpoint is never asked.

Fact by fact

Claude Opus 5.5 and Kimi K3, fact by fact
FactClaude Opus 5.5Kimi K3
Context window1M tokens1.05M tokens
Reads imagesYesYes
PDFsWhole fileText only
ReasoningYesYes
API price (September 2026)$4.00 in / $20.00 out per million tokens$3.00 in / $15.00 out per million tokens
A typical message at API prices (4,000 tokens in, 700 out)$0.0300$0.0225
A $10 top-up adds50 messages100 messages
Where a message goesSent to Anthropic directly.Served through OpenRouter, only by hosts that don't store or train on prompts. The maker's own endpoint is never asked.
If the provider failsIf Anthropic fails before the reply starts (an overload, a server error, a dropped connection), llmwise sends the same request to Claude Opus 5.5 through OpenRouter instead.When one host is down, OpenRouter moves the request to another host that meets the same rules.
Anthropic's safety fallbackAnthropic's safety system can pass a Claude Opus 5.5 message to another Claude model. The reply then names the model that answered and says what you were charged for.Doesn't apply
API prices are what our model catalog lists (Claude: Anthropic's list price; Kimi: Moonshot's list price). In llmwise you pay per message, not per token: the counts above are what you get.

Claude Opus 5.5 or Kimi K3?

From the facts above and our test runs: the rest is how their answers suit your work, which one chat can show you.

  • Pick Claude Opus 5.5: it reads a PDF as the whole file, charts and scans included.

  • Pick Kimi K3: more messages for the money, up to 125 messages a month on Pro; you can try it in the free trial.

Each model's page, the families, and other pairs

Claude Opus 5.5 vs Kimi K3 is one pair of models. The page below covers the whole families.

Questions

Is Claude Opus 5.5 or Kimi K3 cheaper in llmwise?

Kimi K3 gets twice as many messages: up to 125 messages a month on Pro, against up to 62 messages a month for Claude Opus 5.5. Every paid plan's monthly allowance is shared by all models, so each count is the most you get if it all goes to that model.

Can I try Claude Opus 5.5 and Kimi K3 for free?

Kimi K3 is, in the free trial of 5 messages; Claude Opus 5.5 needs a paid plan.

Which has the bigger context window, Claude Opus 5.5 or Kimi K3?

Kimi K3: 1.05M tokens, against 1M tokens. A chat in llmwise holds up to 200k tokens, which fits in either, so the difference shows only through each maker's own API.

Can I use Claude Opus 5.5 and Kimi K3 in the same chat?

Yes. Pick Claude Opus 5.5 for one message and Kimi K3 for the next; the second sees the whole chat, including the first one's answer.

Which did better in your test runs, Claude Opus 5.5 or Kimi K3?

On the same 50 prompts, run on September 27, 2026, Claude Opus 5.5 passed 49 and Kimi K3 passed 46. The table on this page has each job, and every reply is published.

Claude, GPT, Gemini, DeepSeek, Grok, Kimi, and GLM, in one chat.

See what a message costs before you send it. Free is 5 messages to try; sign in with an email link, no password or card.