Drawing in, point data out

How it works

A sounding chart is a drawing: every depth is a placed number with a mark beneath it. The engine reads those numbers straight out of the PDF — as geometry where they are drawn, as text where they are typed — and returns each sounding as a coordinate, a depth and a confidence value. No image recognition, no OCR.

stages
3 steps
charged on export
$75
output
CSV point data
01you

Upload, pick & outline

Drop a vector PDF and a window opens with every sheet down the side. Pick the sheet, then click around the soundings to outline them, leaving out title blocks, notes and tables, or use the whole sheet. Each sheet shows its upload size, and one over 4.6 MB is flagged before anything is sent. A raster or scanned sheet is refused on upload and never costs a conversion.

Pick the sheet
Outline the soundings, or use the whole sheet
Confirm your rights and convert
02engine · seconds

Extraction

Both readers run on every sheet — one for depths drawn as vector strokes, one for depths carried in the text layer — and the coordinate grid is fitted from the sheet's own border labels. Each sounding comes back as a coordinate, a depth and a confidence value.

Detecting sounding marks
Reading digits
Resolving uncertain values
031 conversion

Review, pay & download

The extracted surface opens for review — count, mean confidence and every flagged point, view only, no account needed. Pay once when you're satisfied and the export opens straight away; the conversion is charged here and nowhere else. Download the CSV, and download it again free at any time.

What the engine can read
Vector sounding PDF, one sheet (or one picked from a plan set)supported
CAD or GIS plot exported to PDFsupported
Depths set as text, or drawn as outlined glyphssupported
Scanned raster images and flattened bitmapsrefused
Photographed or copied paper chartsrefused
OCR- or AI-read chartsrefused

A refused sheet is caught on upload, before any processing, and never costs a conversion.

What comes back
easting,northing,depth,confidence
1466412.38,553108.94,7.32,0.981
1466417.82,553108.60,7.41,0.964
1466423.15,553108.27,7.55,0.612
easting, northingReal-world position, georeferenced from the coordinate grid read off the sheet's own border labels. A sheet carrying no readable grid exports page units instead, and says so.
depthDepth as drawn, in the sheet's own units.
confidenceConfidence in the reading, 0.000 to 1.000.
On the roadmap
Contour and isobath lines (depth contours)planned
Whole-number depths, with no decimalplanned
Several sheets of a plan set in one goplanned
More export formats: XYZ, DXF and DWG for CAD, LandXMLplanned

Planned, not dated. Today each conversion reads one sheet of a vector PDF and exports CSV.

How confidence is banded

Confidence describes the reading, not the survey

A point at 0.99 means the digits and the mark were unambiguous in the drawing. Positional and vertical accuracy can never exceed that of the drawing you supplied.

≥ 0.90
clean read

Passes through untouched.

0.70 – 0.89
crowded

Overlapping labels or contour crossings; worth a look in the review.

< 0.70
flagged

Listed individually for review, before and after purchase.

Vector sounding PDFs only. Scanned raster images, flattened bitmaps, paper charts, and OCR/AI-read charts are not supported.

For Tender Estimation & Verification Only. Extracted datasets are not certified hydrographic products and must be verified by a licensed professional surveyor prior to field operations.

Try it on one chart

Upload, extract and review at no cost. You pay $75 only when you export.

See pricingStart conversion