Sadler reached the landmark as Town drew 2-2 at home to Peterborough on Saturday, which was also his 500th career outing.
Now 33, the centre-half has made no secret of his aim to become a manager in the future.
But he feels he has plenty left in the tank as a player and wants to surpass 300 games in blue and amber.
“It fell nicely. I’m chuffed to bits with that, I would’ve liked it to have been on a win, of course,” said Sadler.
“But all my family were there and I’m really chuffed to firstly get to that 200 milestone.
“I said after my 100th that I’d be really desperate to get to 200 as quickly as I can and I’ve got here reasonably quickly.
“And now you’re looking at the next milestone, get to 250, get to 300.
“I’m chuffed to get to 500, it’s a nice marker and milestone. And then you set the next target – 600.”
Sadler had a loan spell at Salop in 2010/11 before joining the club permanently in 2015.
He has made the transition from left-back to centre-half over the past few years.
“People don’t seem to stick around at clubs these days, do they? I’ve just been grateful that (Shrewsbury have) had me for 200 games through the ups and the downs,” he said.
“I’m pleased it’s 200, I’d have been chuffed to bits to see that game out.
“But personally it was nice to have my family there, my children and wife, it was nice but tinged with a little disappointment (that we didn’t win).”
And Sadler believes good times are ahead under Sam Ricketts.
“It feels like there’s a manager here who’s desperate to do well,” he added.
“It’s an environment desperate to succeed.
“Those things in place are always the bedrock of achieving, that’s how it feels.
“That means we have to put a lot of hard work out on the training pitch to get to that but it feels that way.
“We are happy to go toe-to-toe with anyone in the division, especially at our place, I don’t think many teams fancy playing us (at the Meadow) because we’ve got some real energy, some real legs.”
Sadler swept the board at Town’s end-of-season awards in the summer.
His current Salop deal is due to expire next summer.