About Your Friendly Developer
Last updated: April 16, 2026
Hi. I’m Jason Ramirez, the founder and only developer behind FiberTools.
I built this site about a year ago for a simple reason: every fiber arts calculator I tried solved one problem and ignored the rest. I was constantly switching between five different tools — one for gauge, one for yardage, one for pattern conversion, one for stitch counts. So I built one tool that does all of it.
FiberTools is a working maker’s toolbox, not a content site with a calculator bolted on. I use it every day. The pages get updated when I find something missing.
About FiberTools
Not every tool I build comes from personal crisis. Some just come from noticing a gap. FiberTools came from watching how scattered and inconsistent the information was for fiber artists trying to do basic calculations — yarn yardage, gauge conversions, needle sizes across international standards.
I built this the same way I’ve built everything: researching until I understood it well enough to make it useful for someone else. Every calculator is grounded in Craft Yarn Council (CYC) standards — the same classification system used by yarn manufacturers worldwide. The yarn weight system (0–7, Lace through Jumbo), recommended hook and needle sizes, and gauge ranges all follow CYC published specifications. The needle and hook conversion tables map US, metric, and UK sizing using manufacturer standards, not approximations.
I verified every formula by hand before deploying it. Each calculator was tested against edge cases: extreme blanket dimensions, non-standard swatch sizes, stitch patterns that don’t divide evenly into the target count. The increase/decrease calculator’s distribution logic — spreading leftover stitches evenly so the spacing looks balanced rather than lumped at one end — took three rewrites to get right, because the naive approach produces results that experienced knitters immediately notice are wrong. The blocking calculator accounts for fiber-specific growth rates, because wool blocks differently than cotton, and a tool that ignores that distinction isn’t actually useful.
I’m not a fiber artist. But I spent real time learning the craft well enough to build tools that fiber artists trust. That gap between “technically correct math” and “actually useful for someone holding hooks and needles” is where every design decision in this project lives. Every tool is free, ad-supported, and built to stay free.
Built by a developer who respects the craft, even if I’m not the one holding the needles.
Get in Touch
Have a suggestion, found a bug, or want to request a new tool? I’d love to hear from you.
Email: hello@fibertools.app
I read every message and do my best to respond within a few days.
Jason Ramirez / Your Friendly Developer LLC