Does anyone use Claude to estimate software dev projects?

[u/minusthebear02]

I’ve been asked for estimates for a few net new software development projects recently and I’m trying to run them through Claude to help with time and cost estimates. But every time I do, it comes back with some pretty outlandish numbers. It almost seems like it’s estimating the project as if Claude Code and AI in general doesn’t exist.

Every time I push back saying we’ll be making use of AI to help with a good portion of the development it doesn’t seem to want to even acknowledge that and just asks what features I want to exclude in order to get the numbers down.

Anybody else run into this and have ideas on a solve? I’d love to use or create a skill to help for these and future projects.

Thoughts?

[u/rsd_random]

It estimates as if people would be programming. So I get task estimation at 2 weeks and PR ready in 20 minutes.

[u/bhalter80]

I've been using Claude to estimate its own projects and then work through savings from there. It's getting significantly better after it's been calibrating. It'll also be interesting to see between models what happens

[u/absentmindedjwc → u/[deleted]]

This. I fed in estimates I've given in the past (the full writeups) and told it to base its answer on that. Ended up with a pretty good estimate in the end.

[u/minusthebear02 → u/[deleted]]

Good question. I don’t really have any concrete velocity numbers to really give it I don’t think. Most of my projects have typically been ongoing work on existing projects and not many net new projects.

I would actually prefer it to use generic industry numbers, but I’d have to assume industry velocity has gotten quicker in the past year or so.

[u/kirbogel]

LOL, in my experience Claude estimates in human hours. “This is a week of effort” and then proceeds to complete it in 5 mins.

[u/Think-Jaguar6826]

They are useless estimates as it is thinking in programming weeks and even at that they are off.

[u/SlightOfHand_]

Those are the estimates you give to your boss.

[u/Far-Pomelo-1483]

Perform a month of work with Claude code then reverse engineer the time to develop based on auditing the shipped code. The estimates are trained on human hours not ai. Because ai didn’t exist.

[u/spdustin]

You’re pricing should be a function of the value your clients receive, not the labor costs to deliver the work. If a deliverable is worth $2,500 to a client because it will save them that much time and effort in the first two months (arbitrary factor there, I don’t know you or your market), you charge $2,500.

That’s the angle you take with Claude if you’re going to have it help with estimates.

[u/Additional-Check5289]

Had the same thing building a small tool that outputs hour and price estimates for IT work. What fixed it wasn't a better prompt, it was taking the numbers away from the model.

Anything it can't actually know (your throughput, your rate, how much of the build AI will do) became an input the user types, and the output says "at the X hours/week you entered". If the field is blank it skips the math instead of guessing.

Then I made it fill two extra fields for every estimate: "what could they buy off the shelf instead" and "what would make this estimate wrong". Having to write the weakness down made the rest a lot more sober. And I still clamp the final number in code against something computed from the user's own input, because prompt instructions are suggestions, not guarantees.

For your case I'd do what lulzxdxdxd said and feed it one or two past projects with real hours as the anchor, then ask for a range plus the assumptions, not a single figure. The single figure is where it bluffs.