check and improve health & speed

Hi,

Since a long time our website seems to be very slow.

We have tried several things like more expensive hosting, optimized theme and installming a bunch of plugins which resulted in multiple terrabytes diskspace because of chaching plugins while our hosting is 50Gb.

Is there a plugin or service, so we can detect what is wrong with our site. For one, the speed is horrible and there is not that much content anyway. Can be free or paid, does not matter, we want better results.

Thank you in advance,

Roger

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