ToolGrit: Free Industrial Calculators Built by Someone Who Actually Uses Them

I’ve spent more than to two decades working in industrial maintenance, research labs, and field operations. Mud logging in the Bakken, core analysis at a research facility, and now electrical and instrumentation planning at a sugar processing plant. One thing that never changed across all of those jobs: when you need a quick calculation, your options are either a $200 software license, a spreadsheet somebody built in 2003 and nobody remembers how it works, or doing the math on scratch paper next to your coffee.

That’s why most of my built effort recently has been focused on ToolGrit.

What It Is

ToolGrit is a collection of over 200 free online calculators covering trades and industrial work. Electrical, HVAC, agriculture, water treatment, machinist work, drilling, emissions, safety, and more. No login required. No ads. No app to download. You open the page, plug in your numbers, and get an answer.

Every tool runs right in your browser. There’s nothing to install, no account to create, and your inputs stay on your device. The calculators cover real tasks that tradespeople, operators, planners, and engineers deal with on a daily basis.

Who It’s For

If you’ve ever needed to figure out conduit fill, size a transformer, estimate concrete for a pad, calculate pump flow, or work out evaporation losses on a holding pond, these tools were built with you in mind. The target audience is the person standing in a control room, a shop, or out at a job site who needs a reliable answer without digging through a textbook.

Categories include:

• Electrical and NEC code calculators
• HVAC load and ductwork sizing
• Water treatment and municipal utilities
• Agriculture and grain storage
• Machinist and fabrication tools
• Emissions and environmental compliance
• Industrial safety and maintenance planning
• Geology and drilling calculations
• Residential estimating

Why I Built It

Most online calculator sites are either loaded with ads, limited to a handful of tools, or clearly built by someone who has never worked in the field. I wanted something that covered the range of calculations I’ve actually needed across different industries, with clean results and no nonsense.

The tools include PDF and CSV export so you can save your work or hand it to someone else. Many of them generate shareable URLs, so you can send a specific calculation to a coworker with all the inputs already filled in (this is done with a coded link not tracking). There’s also a Pro tier for $6, $15, and $200 a year if you want to support the project, but the core tools are free and staying that way.

Built Different

Every calculator gets checked against published references and known values before it goes live. The math matters. If a tool gives you the wrong wire size or the wrong pressure drop, that’s not just an inconvenience. I treat accuracy the same way I treat it at work: verify it, then verify it again.

New tools get added regularly. If you work in trades, maintenance, engineering, or operations, take a look. Odds are there’s something in there you’ll use this week.

If you don’t see what you want let me know. 

Free DuPont Schedule Generator – Simple 24/7 Shift Planning

I put together this DuPont Schedule Generator in Excel to make my own shift planning easier and since I don’t use it anymore, I’m sharing it here for anyone who might find it helpful.

The DuPont shift schedule is a rotating 12-hour system that provides continuous 24/7 coverage, with a nice bonus of a full week off every cycle. If you’re using this kind of rotation, this tool makes it easy to visualize your schedule at a glance.

How It Works:

Just open the file and enter a start date  the first day of a set of four consecutive workdays right before your week off. The rest of the year will auto-fill based on that start point.

What You’ll Get:

• A clear, color-coded layout

• A full-year overview at a glance

• No formulas to mess with — just plug in the date and go

It’s completely free to download and use. I built it for myself, but maybe it’ll save you a few headaches too.

Let me know if it comes in handy!

Thoughts on the Tesla’s Run at the Green Hell (Nürburgring)

Everyone but Porsche seems fairly impressed with Tesla’s plaid prototype.  Today they announced that their unofficial laps times are in the neighborhood of 7 minutes 20 seconds.

They also said they think they may be able to get the time into the 7:05 range next month when they are back to try again.

What I don’t see anyone talking is what the ultimate purpose is for being at the ring in the first place.  Yeah Porsche… made fun of a 6 year old car. That’s not the goal.

Predictions: The Next Time We See Tesla at the Nürburgring

1. Tesla Model S Plaid will easily set the fastest (soon to) production four door car speed around the track. They will use the data from this run to tweak the car.
2. They may also set the quickest mass produced cars self-driving/autonomous speed time on the track.
3. The first trip was all just smoke and mirrors so than can collect data for their real run at the Nürburgring.
   1. Who cares if you’re the fastest four door car at the track? The real goal is fastest car around the track ever. Period
4. … The Roaster 2.0 should be out sometime late next year. Maybe They will bring the Roaster 2.0 the next time they show up at the track.

Tesla’s Hype Machine

Tesla lives on hype and the following quote is directly from the preorder page for the Tesla Roadster 2.0.
“The first supercar to set every performance record and still fit seating for four.”

A run at the Ring would help solidify their claim if the car is up to the task.  With the data they collected on this trip they can probably figure out the Roadsters 2.0s. theoretical lap time.

According to Wikipedia, the current production car record holder is the Lamborghini Aventador LP770-4 SVJ @ 6:44.97.   Lamborghini conducted test with a full roll cage and Pirelli P Zero Trofeo R tires.

According to the information released by Tesla, the Roadster 2.0 should be able to out preform the Aventador LP770-4 SVJ in every way.  Time will tell if that statement is true.

Wrapping things up

The long and the short of it…  Tesla was at the Nürburgring for two reasons.

1. Repay Porsche for trying to embarrass them on the world stage.
2. Collect data to get their Tesla roaster dialed in for a run at the all-time production Nürburgring record attempt.