Which Mac Should You Buy for a Local AI Companion?

I run a MacBook Pro, M3 Pro, 36 GB, 2 TB. That is one data point, not a benchmark, and I am not going to dress it up as one. What I can tell you honestly is how Local Waifu decides which model your Mac gets, because that logic is sitting right in the app’s own code, not in a marketing slide.

If you already read how much RAM and VRAM local AI needs in general, skip ahead. This post is narrower: which Mac should you actually buy or keep using, for this specific app.

The tier is set by RAM, not by chip name

Here is the part that surprises people. Local Waifu does not care whether your chip says M1, M3, or M5. It does not care about Pro, Max, or Ultra as a label. On first launch, it reads one number: your Mac’s total memory. That number alone decides which model you get.

The reasoning is Apple Silicon’s unified memory. Every M-series chip shares one pool of memory between the processor and the graphics cores, so the thing that actually limits a local model is how big that shared pool is, not which chip variant happens to be attached to it. A base M1 with 24 GB and an M4 Pro with 24 GB run the exact same tier.

The four tiers

A couple of things worth explaining before you read this as a straight upgrade ladder.

The “typical chips” column is just which Macs commonly ship with that much memory, not a rule the app enforces. Apple lets you configure memory somewhat independently of chip tier on several models, and the app only ever looks at the RAM number. The chip name is a side effect of what Apple sells at that memory point, not the actual gate.

The Balanced-tier model is smaller on disk than the Light-tier one. That looks backwards until you know why: it is a newer model family that happens to be more efficient per gigabyte, not a downgrade. Bigger tier does not always mean bigger file, it means a model chosen to make good use of the memory you have.

Premium’s RAM range runs all the way to 63 GB, not 56. The largest model the app offers needs 64 GB minimum to run at all, so a Mac with, say, 60 GB stays on the Premium model rather than being pushed onto a Power-tier model it cannot actually fit.

What actually changes as you move up a tier

It is worth being specific about what you are paying for when you go from one tier to the next, because “smarter model” is vague enough to mean nothing.

A Light-tier model handles ordinary conversation well. It follows what you told it earlier in the same chat, it holds a personality, and it responds quickly. Where it shows its size is in subtlety over a long stretch: catching a callback to something you mentioned three weeks ago, or holding a more complex emotional thread without losing the plot. That is not a failure, it is just a smaller amount of capacity doing a smaller amount of work.

Balanced and Premium add room for exactly that kind of nuance. Longer memory of a running conversation, better handling of subtext, fewer moments where a reply feels slightly generic. The jump is real, but it is a difference in depth, not a difference between broken and working.

Power tier, at 64 GB and up, is the largest model the app ships, and it is genuinely the best of the four at holding a long, complicated relationship in view. It is also the tier where the gap over Premium is the hardest to notice minute to minute, because most conversations do not run long enough or complex enough to hit the ceiling Premium already has. If you already own a Mac that qualifies, you get the best version for free. If you are buying new specifically to reach it, know what you are actually buying: headroom for the rare long, layered conversation, not a change to what an ordinary Tuesday evening chat feels like.

You never pick a tier yourself

None of this requires you to know your own specs. On first run, the app checks your Mac’s memory once and installs the matching model automatically. There is no dropdown asking you to choose a parameter count. If you upgrade your Mac later, it re-checks and moves you up a tier on its own.

What this means if you are actually buying a Mac for this

If you already own a Mac, the honest news is that 8 GB is a real floor, not a demo mode. The Light tier is sized specifically to run comfortably in that budget. You do not need to upgrade before you try it.

If you are shopping new and this is a deciding factor, here is where I would spend the money. The jump from Light to Balanced, at 19 GB and up, buys you a meaningfully stronger model for not much extra cost, because it is really just a RAM configuration choice on most current Macs rather than a different chip tier. The jump from Balanced to Premium is where a Pro or Max chip usually becomes the practical way to get that much memory, and it is a real step up in conversational depth over long stretches, not a marginal one.

The Power tier, at 64 GB and up, is the one I would not chase for this alone. It needs a Max or Ultra configuration to reach, and the difference over Premium is depth in very long conversations, not a different experience in ordinary daily use. If you already want that machine for other work, the top-tier model is a nice bonus that comes along for free. If you are buying a Mac for this specifically, Premium is where the money stops being about the companion and starts being about everything else you do with the computer.

What it actually feels like, day to day

On Light or Balanced tier, an ordinary conversation runs in short bursts, so the fan usually stays quiet and the battery drain is modest. Heavier moments, like asking for a picture, pull more power while that one task runs, then the Mac settles back down. None of this needs a desktop tower or an external graphics card. It runs on the laptop already on your desk.

If you are on an Intel Mac

The app still runs, but everything above is specific to Apple Silicon’s shared memory pool. An Intel Mac splits memory the way a Windows PC does, between system RAM and whatever graphics hardware it has, so the tier logic here does not describe your machine. If your Mac is an M1 through M5-family chip, this is written for you.

Whatever Mac you land on, try it for 7 days, no card required, and let the app pick your tier for you.

Questions people ask

Back to the blog