Which model is likely better as a "professor" if you will. One who understands, corrects me, helps editing work on accuracy, gives writing suggestions, etc.

They consistently state: We recommend switching to Sonnet 4.5, which now offers: Better coding performance than Opus 4.1

I'd like to see a vote or get a sense of what people are seeing in real situations.

I feel like still get far better results from Opus.

Thoughts?

Curious to know what is other's experience using these models? I feel like even with Max plan, i am forced to use Sonnet 4.5 - but holy fuck it's stupid compared to Opus 4.1, it's a fucking moron, cute and funny one, but its IQ can't be above 70. Nevertheless, at least he's a great little coder, when u tell it what to do and test its results comprehensively.

Do you use Opus or Sonnet, and why? Any tips/tricks that makes Sonnet smarter?

I've been using fully Claude Opus 4.1 in my terminal setup for coding, reasoning, and agent-like tasks. it's been solid for complex workflows. But now that Sonnet 4.5 is out, I'm wondering if I should switch. From benchmarks, it seems to match or beat Opus in areas like coding (higher scores on SWE-Bench and agentic tasks), visual reasoning, and handling nuanced instructions with better efficiency for iterative sessions. If you've tried both in a CLI/terminal environment, what's your take? Does Sonnet hold up for deep reasoning and long-chain planning, or does Opus still edge it out there?

For complex workflows, would you recommend switching? Experiences appreciated!

Hi all - long time Claude & CC user.

Have had only positive things to say about the product so far, Claude Code in particular. The Anthropic team have built an incredible tool that has fundamentally changed my day-to-day as an engineer. My experience is as a Max x5 subscriber and I work on a large, well established code-base.

Just a bit of commentary on my experience with Opus 4.5 for Claude Code and am looking for some feedback from others on their experience so far. I hesitated to make this post, as I think there can be a bit of a tendency to pile-on and not give the team time to resolve issues.

In the early days, I was a heavy Opus user. Would often hit session limits, but usually not too long before the refresh so only typically waiting about an hour. For the cost, waiting this length of time was fine. The introduction of stricter limits, including Opus and weekly didn't affect me even though I use near-daily and often across 3 sessions in a day. I found Sonnet more useful, basically have never hit a session limit, and not once have hit a weekly limit. This has been, for me, a perfect workflow for sometime. Sonnet 4.5 has to be my favourite model to date - context seems large, it always knows where to look, where to edit and does it all unbelievably quickly.

I am not having a similar experience with Opus 4.5. I know it has been a day, so I might be saying this too soon, but my worry is that this model is an 'Opus' only in name. The structure and language of my prompts don't seem to resonate with Opus in the same way as Sonnet. Just this evening I've gone around in circles trying to feed logs from a server to validate a recent change. Opus stood no chance. It was explaining: the concept of logs to me, the structure of the endpoint, the endpoint itself, when the endpoint should be called. I change models, to Sonnet, and ask it to simply 'try again', it validates, finds the issue and presents me the change I was after.

I'm sure, as with all models before it, I'll get use to this one eventually too. I would love to know if anyone is facing similar issues or if they have any tips particularly for large codebases that have helped Opus 4.5 succeed.

Anthropic says the sonnet 4.5 is the smartest model out there outperforming opus 4.1 . I switched to newer model thinking well it should be better. However yesterday when using it sonnet has wasted my time unable finding a bug (4-5 prompts), while opus 4.1 found it with one prompt. it was a simple bug where I had to remove '_' from the string inside.

the opus 4.1 seems to be more attentive to details than sonnet . it seems sonnet is more logical, the way it writes code, what approaches uses.

I’m on the $100/month plan. 1-2 prompts in I got my limit on Opus, then I spend most of my coding day on Sonnet.

Whenever I am on Opus, it isn’t obvious it’s writing code that Sonnet can’t. I see a bigger difference between prompts that do vs. do not have “ultrathink” rather than Sonnet/Opus.

Does anyone with more experience have a clear perspective on Sonnet vs Opus? Even on the benchmarks they are about the same.

Heeyyy guys, I’ve been messing around with Opus 4.5 recently, and I’ve noticed it can do a lot more than Sonnet 4.5. It’s not necessarily because it’s smarter, but because its knowledge base is way more up to date. For example, Sonnet 4.5 didn’t even know iOS 26 existed, and it kept suggesting old, deprecated methods, which caused a lot of issues for me.

Opus 4.5, on the other hand, writes code faster, costs the same as Sonnet, and handles multitasking way better. It honestly feels like they just refreshed the knowledge base, gave it a bit more power, and made it more efficient with tokens.

Overall, I think it’s a big upgrade compared to Sonnet 4.5, not because it’s more intelligent, but because it’s newer. That has just been my experience though. I might be wrong 😭 Curious to hear how it’s been for you all.

Not sure what's going on, but I've noticed that when using Claude Opus 4.5 in a project, particularly for help on my writing that uses Google docs for the reference files, character summaries, etc. Opus not only doesn't research the files in the project, but it hallucinates heavily, getting my characters completely wrong and making stuff up overall.

Meanwhile from the same app, in the same project, Sonnet 4.5 works flawlessly, referencing the files and staying consistent with my characters.

Not sure if it's an oversight but has anyone else experienced this? I'm just bummed because I usually use mobile when I can, and it looks like I'll have to continue using Sonnet on mobile until they fix it.

Hi,

after the rate limit shock, opus 4.1 is not affordable anymore - for me at least. In all of my (large) projects, opus 4.1 is doing a lot of better than any sonnet.

Anthropic wrote: Sonnet with extended thinking is better than opus 4.1.

In my experience, thats not true. It lasts longer to get the same (or nearly the same) result with Sonnet - I need to have more prompts. (I am not talking about easy things - the model needs to check several files, needs to understand the whole project etc.)

So my question is: Is Anthropic right and I am doing it the wrong way? Have I overseen something?

Yes, I have turned on the extended thinking in ~/.claude/settings.json:

"alwaysThinkingEnabled": true

Maybe sonnet 4.5 needs another CLAUDE.md than opus?

I read that its possible now to set includes in CLAUDE.md - maybe the best practise has changed here?

So what is your experience? Any tips?

Is it cheaper is it better? does this mean the cheaper model is now outperforming the expensive one?

How do you compare using Opus vs Sonnet when generating code? Is their a way to quantify, or at least describe, the different results? Are there scenarios where it makes more sense to just use Sonnet rather than Opus? Or should Opus be used 100% of the time, budget permitting?

With Opus 4.1 limits reaching in just about 5 hours of work, is the Sonnet 4.5 model even as good as opus in coding tasks?

I had some time to check out the sonnet 4.5 model (accidentally, as claude automatically switched my model from opus to sonnet), it handled planning pretty well, but not sure of the execution as it made some Average UI. Immediately hit on rewind once I realized it was sonnet working, as I don't usually trust the model in the first few days of it's release, at least not until I have read reviews about it. Opus killed it, but it killed the limit too.

What's your experience with Sonnet 4.5?

I work in quantitative finance, so most of my programming revolves around building financial tools that detect and exploit market anomalies. The coding I do is highly theoretical and often based on insights from academic finance research.

I’m currently exploring different models to help me reason through and validate my approaches. Does anyone have experience using Opus 4 of Sonnet 4 for this kind of work? I’m trying to figure out what is the best fit for my use case.

Hello. I like to use Claude to translate and read Chinese webnovels that have yet to be translated, and I think Opus 4.1's writing is kinda weird, stiff and sometimes too literal compared to its predecessors. Now that Sonnet 4.5 is out, I'd love to have your thoughts on the new model before I renew my monthly payment to Anthropic. Is it better?

How are people genuinely praising Claude Code Sonnet 4.5? I have no idea what’s happening…but from my experience it’s pretty disappointing. Sorry if that stings, but I’m honestly curious about what others see in it.

I’m speaking as someone who uses Claude Code daily easily 7+ hours per day and who has been deeply involved with it since the beginning. I consider myself a power user and truly understand the capabilities it should have. Maybe I’m missing something crucial here…but BESIDES that point I’m really dissatisfied and frustrated with Anthropic right now.

On top of that, the marketing hype around Sonnet 4.5 feels like the same garbage AI slot promotion we saw everywhere with ChatGPT lol. It’s being marketed as the “best model in the world,” likely to people who barely even scratch its surface.

I’ve also just hit a usage limit on Opus 4.1. I’m on the max 200 plan and now there’s some kind of cap in place…for what, a week? Why? If Sonnet is sooooo good why are they placing weekly limits on opus 4.1? So stupid. Can someone explain what’s going on here?

Hey everyone,
I used to rely heavily on the Sonnet 3.7 model for large-scale translation + script generation workflows, and it worked really well for my needs. But since 3.7 is gone, I’m a bit lost and trying to figure out the best replacement.

Right now I’m considering three models: Sonnet 4, Sonnet 4.5, and Opus 4.5. I’m slightly leaning toward Sonnet 4.5, but I’m not sure if it’s the best choice for high-volume script generation with consistent quality.

If you’ve tested these models for similar tasks, I’d really appreciate your insights or recommendations. Thanks!

Hi! I have been using both opus 4.1 and sonnet 4.5 for quite a while (few weeks) and I haven’t notice what’s the best for such scenes.

I know that opus is great and 4.5 is very very amazing but I have no clue which is really good for general use or heavy smut scenes (descriptions, size, sfx, etc.)

For sure that Claude would’ve made 4.5 really good again right? No. It’s not the same as it was and I just prefer 4.1 much more when it comes to smut and 4.5 for dialogues since it’s the best for sonnet.

In short terms: please tell me which Claude model/any model that is the best for smut and why because both models aren’t really the same.

I am using tavo (a mini sillytavern) that’s basically kind of the same without any extension plugin (since I don’t have or own a pc)

I'm not rich enough to know/figure it out.