Claude Haiku 5.5

Pelicans riding bicycles for Haiku at the different thinking levels: https://tools.simonwillison.net/markdown-svg-renderer?url=ht...Low messes up the bicycle frame, but medium/high/xhigh/max all get the bicycle frame right.The max one took 5 minutes 9 seconds and cost 3.3826 cents. The cheapest one (low) cost 0.0936 cents and took 7 seconds.The most recent release of my llm-anthropic plugin queries the Anthropic model listing API directly, so I didn't have to upgrade the plugin to add support for this model: llm install llm-anthropic -U llm anthropic refresh llm -m claude-haiku-5.5 'prompt goes here' EDIT: Here's the Haiku 4.5 pelican from a year ago for comparison, it was terrible: https://simonwillison.net/2025/Oct/15/claude-haiku-45/ reply: thinking_effort: max Reasoning trace: This is the classic pelican-on-bicycle SVG test.Opus 5.5 had similar response on max: This is a classic test requesthttps://tools.simonwillison.net/markdown-svg-renderer?url=ht...I think your test is already embedded into the models. You should search for new frontier tests to subject the models to. Maybe they should now try to unify the standard model and general relativity in physics....

Pricing is...a bit weird. Input $0.10 / MTok for prompts up to 100,000 tokens $0.50 / MTok for prompts over 100,000 tokens Output $0.50 / MTok for prompts up to 100,000 tokens $2.50 / MTok for prompts over 100,000 tokens 100k tokens is an absurdly low cutoff and it is only applicable to Haiku and not Sonnet or Opus. It's a low enough cutoff that it will be quickly exceeded if you are doing anything with Agents; for typical generation or Jev-like classifiers, it's a good value and as noted in this article, that is apparently the vast majority of Haiku use.In both cases, still much cheaper than Haiku 4.5's $1 input / $5 output and these prices better compete with GPT-6 Luna. ($0.10 input / $0.50 output, but with no token threshold [EDIT: the threshold for Luna is apparently 272k]) reply: Haiku 5.5 is noticeably smarter than GPT-6 Luna, so I can see their pricing strategy here.For a while Anthropic has lacked a cost effective “cheap” LLM for summarisation, compacting, RAG helpers, etc.These ‘ephemeral’ workloads are often under 100k tokens, or can be structured to be under 100k.In some coding benchmarks, Haiku 5.5 beats Sonnet 5! (Especially implementation;...

> Second, this week, we’ll roll out a new monthly API credit to all Max and Team subscribers for use on the Claude Platform. Max 5x users will get $100 in credits per month, Max 20x users will get $200, and Team subscribers will receive up to $500, pooled across their usersThis is a very big benefit for me. I can now ship actual ai enhanced features behind my subscription without paying extra or fully relying on on-device models. I do worry that this is to soften the blow for user-unfriendly changes reply: This is them sneaking in taking the Claude Agent SDK (claude -p) off of subscription plans through the back door along with a model release. They previously wanted to do this in June, but backpedaled after huge backlash:https://support.claude.com/en/articles/15036540-use-the-clau...

Ran our DataAnalyticsBench benchmark on it: https://plotly.com/blog/claude-haiku-5-5-plotly-data-analyti...9x cheaper than Haiku 4.5 and 2 letter grades better. It's also now the fastest model (using the default speeds, not trying any of the other models "Fast" mode) to complete the exam.Similar ballpark to Luna in price, cost, and accuracy. These are very cheap models: $0.38 to answer 40 in-depth data analytics questions (compared to $15 for Opus 5.5 or $20 for Astra).Overall very good at data analysis - handling all of the straightforward data analytics questions correctly. It fell short answering some of the questions that required some deeper statistical analysis like looking into other variables. In other words, it's not as persistent as other models in its analysis, which I think we'd expect from how they're positioning the model.Compared to OpenAI: GPT-6 Luna did a bit better and was about 30% the cost of Haiku 5.5. GPT-6.1 Sol got all answers correct, but was 10x more expensive.

My complaint about Haiku 4.5 was that it was 10x the price of GPT-6 Luna.> Claude Haiku 5.5 is priced 90% lower than Claude Haiku 4.5 for requests up to 100,000 tokens, and 50% lower for requests over 100,000 tokensHaiku and Luna now have the exact same price up to 100,000 tokens. Luna is now cheaper for anything after 100,000 tokens, even after Luna's own price increases at 270,000 it's still less than Haiku.So it sounds like they've directly addressed that problem. Their self-reported benchmarks are all higher than Luna too. reply: Yep. I was looking at the prices of lower tier models a few weeks ago for zero/few shot tasks (pre Jev) and Haiku rates just didn't make sense at all. I ended up using 5.6-luna.Good to know that is going back to being an actual option from perf/price perspective.

Ran image -> html tests for this. I was curious if this smaller model was good enough for complex UI. It was not.Haiku 5.5: https://html.non.io/lcars-haiku-5.5/Opus 5.5 for comparison: https://html.non.io/lcars-opus-5.5Designs it was building from: https://diffui.ai/app/canvas/5093e689-1e74-4f26-b632-2a4500f...One interesting thing is it took a look at the job at hand, and immediately delegated it to Opus 5.5. It at least knows what it isn't good at. Very fast though, and likely best used for small subagent tasks / tightly scoped work. reply: Pac-Man Bench:Considering the price, no model comes close to being as good as this. However, it did take an extremely long time.TIME 19m COST $0.16 https://jonclegg.github.io/pacman-bakeoff/#claude-haiku-5-5All results: https://jonclegg.github.io/pacman-bakeoff/

The monthly API credits for Max plan seems fantastic, especially considering Haiku pricing. Being able to actually use my Claude plan for other harnesses and use-cases on top of regular CC usage is everything I wanted.Anthropic has really been doing all the right things in the past few weeks, while OpenAI continues to fumble the bag. reply: Note that this is Anthropic Trojan-Horsing the previously announced June change in with a model release, where the Claude Agent SDK can no longer be used with Claude subscriptions and is now billed with API credits only.https://support.claude.com/en/articles/15036540-use-the-clau...

About time Anthropic released a competitive cheap model. Haiku 4.5 has been too expensive compared to its performance for months now (in fact I don't remember being too impressed even when it was released). This one actually looks worth using in some scenarios. If it's really as much of a step up from Luna as the benchmarks they've shown indicate, it'll probably replace Luna in my workflows. 100k tokens is a pretty low threshold before the price goes up, but I tend to use these smaller models for smaller tasks anyway.

This is great! Been using GPT 6 Luna for decompiling my childhood favorite game (Age of Mythology) and this means I can throw Haiku into the mix as well. 17352/21965 functions matched so far...

Some attempts to benchmark and compare LLM's:https://artificialanalysis.ai/https://benchlm.ai/https://tokenscost.comhttps://www.vellum.ai/llm-leaderboardAre there any projects out there for doing something similar?

I compared the costs between luna and haiku for some classification work. Luna comes out a fair amount cheaper due to more efficient tokenization and less outputs. Model input tokens output tokens batch cost sync cost Haiku 5.5 11,893,643 240,451 $0.21 $0.42 gpt-6-luna 7,903,468 177,602 $0.16 $0.31

At work we use haiku 4.5 for a handful of latency sensitive tasks that are fairly simple. It performs well. Just started testing 5.5 as I’ve been anticipating a nice improvement since it was teased. Results so far are trash. Prompt leakage even. And it’s slower. I guess it’s cheap but I think they got the balance wrong on this.

It's around Qwen-3.8, and Sonnet 5.5 level, but a lot cheaper. It is also really fast.My tests for Haiku 5.5: https://aibenchy.com/compare/anthropic-claude-haiku-5-5-xhig...Twice as expensive as Luna, but also considerably smarter too:https://aibenchy.com/compare/anthropic-claude-haiku-5-5-xhig...

My weekly limit __on a Pro sub__ has not gone over 50% since before the pre-Fable promos, but usage has been pretty much the same from my point of view. Maybe I am holding it right? Anyone else getting this?As such, I do not need to even reach for Haiku, and 4.5 was so inaccurate that it often cost more to do so in the past. Sonnet 5.5/low has been good for this kind of thing, and i didn't even touch thinking tokens or any of that. Opus 5.5 low for questions/repros, medium for implementation, basically never reaching for anything above that anymore. 5.5 has been great, so I'll try Haiku, but don't see myself going out of my way to integrate it.

I wonder if we have an AI LLM equivalent to Moore's Law. Like how often do we expect improvement in this technology and with what timing?

https://www.anthropic.com/claude-haiku-5-5#further-updatesThis section makes the reader think: why would I not pick Sonnet 5.5 instead of Haiku 5.5?

Tested on my RAG system containing all of cloudflare docs (more than 3000 A4 sized highly technical documents): best `quality*speed/price` ratio of any other model. And I have tested more than a 100 different models.

> Claude Haiku 5.5 is our fastest model to date at each model’s standard speed, although it runs less quickly than our Opus models in Fast Mode.Opus 5.5 runs 117 tps average on Openrouter, so it must be at least 10-20 tps slower for them to mention. IDK why they mention this as it does not help for marketing though. https://openrouter.ai/anthropic/claude-opus-5.5

Top of the page in 17 minutes? Now I know what y'all do while your agents are working.

Good to see Anthropic back alternative OSes.

131tok/s P50 according to OpenRouter currently, though might move up or down over the coming days. If it sticks at that speed, roughly twice the throughput of Luna and far lower latency (up to 2sec depending on provider) is impressive, though the 5x price increase beyond 100k is painful.Was a big fan of Haiku 4.5, though understand why for most Sonnet was the far better option back then.

> we’ll roll out a new monthly API credit to all Max and Team subscribers for use on the Claude Platform. Max 5x users will get $100 in credits per month, Max 20x users will get $200They’re definitely planning to make the subscriptions API based so they can charge you full price.

From these selected benchmarks, it looks like it smokes Luna capability-wise. Excited to put it through its paces

It fails the "How many r's in ?" test.I ask:> how many r's in diminishedIt answers:> Diminished has 1 r.

At a glance, looks competitive on the pareto. I hope it retains the flavor of sonnet 5.5 and opus 5.5. Both are extremely good and productive. I have had a lot more issues with gpt 6/6.1 and getting what I want out of them.

I used to always use glm or deepseek instead of Haiku, but now I want to give it a try.

The forgotten model is back on the map. I actually got OK mileage when I tried it for coding months ago. Maybe I'll try it again, with Opus guiding it, and see how it goes.

> Second, this week, we’ll roll out a new monthly API credit to all Max and Team subscribers for use on the Claude Platform. Max 5x users will get $100 in credits per month, Max 20x users will get $200, and Team subscribers will receive up to $500, pooled across their users. These credits are designed to allow our users to experiment with building tools, apps, and agents that call our API.This is kind of nuts