I tracked one full canning season to the jar. Here is what a quart of home-canned tomatoes really costs.
The costs nobody counts
Jars are reusable, but lids are not. Add the energy to run a water-bath or pressure canner for hours, plus the tomatoes themselves if you did not grow them all.
Where it wins
Grown from your own garden, canned in bulk, with reused jars, the per-quart cost lands well under the grocery equivalent — and the quality is not close.
Where it loses
Buy the tomatoes retail, can small batches, and value your time at anything, and you are canning for love, not savings. Both are valid. Just know which one you are doing.