Work out what your radius is costing you per week

Why nobody knows this number

Fuel lands on the fuel card. Tyres land on a receipt. Servicing lands in the diary. Two hours a day behind the wheel lands nowhere at all. There is no invoice, no line item and nothing to point at — it just quietly makes the week shorter and the money worse.

So the radius decision gets made on feel. It’s an hour’s work to make it on arithmetic instead, and you can do the whole thing on the back of a docket book.

The 3 numbers, and where to get them honestly

You need an average one-way drive to a job, a jobs-per-week count, and your charge-out rate. Guessing the first one is where this falls over, because a guess tends to come in low. Do it off the odometer instead.

1. Pick a normal month. Not the December week you did 4 jobs, not the flood week you did 22.
2. Total work kilometres for that month. Odometer at the start, odometer at the end, minus anything that clearly wasn’t work.
3. Divide by the number of jobs that month. That’s your round trip per job, and it includes the wandering — the wholesaler, the second trip back for a part, the drive home at the end.
4. Halve it. That’s your average one-way drive.

The odometer figure often comes in above the guess. The odometer doesn’t have an opinion about it.

Jobs per week is the easier one, and the trap is counting quotes as jobs. Count the ones you invoiced. If you did 41 invoiced jobs across that month, call it 10 a week and move on — this doesn’t need to be exact to be useful.

The charge-out rate is whatever you’d bill an hour of labour at, not what you clear after costs. It’s there to convert hours into something you can compare against a decision, so use the number you already quote from.

The arithmetic, with the assumptions stated

Two assumptions go into this and you’re entitled to argue with either. We use 45 km/h as an average across suburban roads, which allows for lights, roundabouts and school zones rather than pretending you hold the speed limit. And 46 working weeks a year, which leaves 6 weeks for public holidays, leave, weather and the days you write off.

Take a sparkie with a 30 km average one-way drive doing 10 jobs a week. Made-up numbers, real arithmetic.

• 30 km each way is a 60 km round trip per job.
• 60 km × 10 jobs = 600 km a week.
• 600 ÷ 45 km/h = 13.3 hours a week behind the wheel.
• 13.3 × 46 weeks = 613 hours a year.
• At a 38-hour week, that’s 16 working weeks a year spent going nowhere.

Sixteen weeks. Not 16 days. That’s the number that stops the conversation, and it’s the same arithmetic whether you’re a sparkie, a chippie or a plumber — only the inputs change.

Now change one input

Hold the jobs at 10 a week and move only the average drive. Same trade, same customers, different patch.

Average one way	Round trip	Hours a week	Hours a year	Working weeks
12 km	24 km	5.3	245	6
20 km	40 km	8.9	409	11
30 km	60 km	13.3	613	16
45 km	90 km	20.0	920	24

Between the 30 km row and the 20 km row there are about 204 hours a year. At a $120 charge-out rate that’s about $24,500 of capacity, and it costs nothing to create. No new van, no apprentice, no extra advertising.

The honest caveat, because it matters: those hours are only worth about $24,500 if you can fill them with billable work. If the phone isn’t ringing, tightening the radius gives you 4.4 hours a week at home instead, which is a different kind of win and not a worse one. What it never does is give you nothing.

Check it against the calculator

Now that you’ve done it by hand, put the same 3 numbers into the drive time calculator and watch it produce 613 hours. It runs in your browser, nothing is sent anywhere, and there’s no email form on it.

The point of doing it by hand first is that the tool then confirms something you already understand instead of handing you a figure you have to take on trust. Slide the drive distance down and you can watch the yearly total fall in real time. That’s the same table above, with your own inputs in it.

What this number deliberately leaves out

No fuel, no tyres, no servicing, no depreciation. Not the extra 20 minutes when the motorway backs up. Not the 4 o’clock job you turned down because you were already 40 minutes the wrong way, which can be the most expensive item on the list.

All of those are real and all of them make the figure worse. They’re left out because putting a number on them means guessing at your ute, your fuel bill and your week, and a guessed number is exactly the thing we’d tell you not to trust from anyone else. So this counts hours only, and values them at a rate you set yourself. It’s the smallest honest version of the number. The real one is bigger.

What to do with the answer

The figure isn’t an argument for turning down work. Nobody can afford to knock back a job they need, and a tradie who starts saying no before the close work exists just has a quieter week.

The useful framing is the other way round: get enough work close by that saying no to the long ones costs you nothing. That’s a denser net inside a smaller area, not a wider one.

It’s an argument for a different job mix. A $90 powerpoint 40 minutes away and a switchboard upgrade 8 minutes away take the same slot in your week, and one of them pays for the week. Getting enough of the close work means being findable in the suburbs either side of your own, which is a question about where you show up on the map rather than about how far you’re willing to travel.

So run the number first. Then decide which suburbs are worth committing to, and be honest about which ones you’re only servicing because the phone rang once.