BLOCKPREP marker

0 blocks
Load a screenshot, then drag to draw a block.
Pick its type on the left first. Click a block to select & name it, Delete to remove.
Nesting is automatic — draw a box inside another.

Export

Numbered image + matching JSON. Blocks you ticked Read get transcribed by Claude into their own tabs.

annotated screenshot with numbered block regions
or right-click the image → Save
image + block JSON (+ a crop of each block you're reading) — sent to S3 and built into a workbook