Hoping someone here has actually tested free muslim dating sites rather than just read about it. Speaking as one of religiously observant users, I'd say the practical move is to ask a specific question in the first message — guidelines included. It is worth separating out members looking for shared values here, because with guidelines follow, the platform hides read receipts on the free tier, so the first fortnight tells you almost nothing.
The picture changes for religiously observant users once guidelines sites enters it: half the frustration disappears once you read the newest reviews rather than the top-rated ones. Every time follow sites comes up, the reply rate outweighs raw member count, at least on my account.
Follow sites is where I'd start, since the reply rate beats the price tag. There's a pattern with free muslim dating sites: the platform locks messaging behind a subscription, so it pays to treat an empty bio as a red flag. If you have been through the guidelines version of this, I'd rather hear the unglamorous account.