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An easting and a northing are metres inside one 6-degree zone, so without the zone number and the hemisphere letter they are not a location. Read one zone over and the same pair lands 611 km away; type the northern letter and the converter drops it for zones 17 to 25, which is exactly Brazil.
SIRGAS 2000 and WGS 84 are the same place to within a metre, and PROJ transforms between them with a no-op. The pair that moves your data is the legacy one: at Brasília SAD 69 sits 68.530 m from SIRGAS 2000 via EPSG:15485, and at Belo Horizonte Córrego Alegre sits 41.711 m away via EPSG:6193.
Nine degrees-minutes-seconds forms through the coordinate converter, measured: which parse, which come back as DMS format not recognized., and which are accepted and still wrong. Plus the spreadsheet formula that fails silently, GDAL exiting 0 with no points, and one DMS cell in the csv-viewer.
A point at (0, 0) is not a place your data came from — it is a coordinate that went missing, got swapped, or was read from the wrong column. Four failures, each reproduced in the csv-viewer and the coordinate-converter with the message the tool actually shows, the distance it costs, and the fix.
No .prj, so nothing knows what the numbers mean: GDAL prints no CRS, QGIS asks, and the browser viewer assumes WGS 84 and says so. How to tell degrees from UTM metres by looking at the numbers, why an exported longitude of -2171693 is your easting, and the two ogr2ogr lines that fix it.
No .shx and GDAL refuses while the browser opens the file; no .dbf and everything opens with zero attributes and no warning; no .shp and there is nothing to open. What each Shapefile file is, whether it can be rebuilt, and what the viewer and ogrinfo say for each missing one, measured on IBGE data.
Verified list of free geospatial data for Brazil: IBGE meshes and census tracts, INPE's PRODES, DETER and fire hotspots, MapBiomas, ANA hydrography, conservation units, indigenous lands, roads, mining and power plants. Every link tested 15 September 2026, format, measured CRS and licence as printed.
The dBase header gives a Shapefile field name 11 bytes, one a terminator: 10 characters. GDAL warns and cuts, colliding names become nome_da_un, nome_da__1 and nome_da__2, and the viewer shows the short one. On GDAL 3.13.3 a complete .shp.xml restores the name; a partial one is ignored silently.
Three columns, lat and lon, dropped into the csv-viewer — that is the clean case. This post covers the others: the decimal comma Excel pt-BR writes, a title row that shreds every line, swapped columns that draw silently in the wrong ocean, DMS, UTM and Latin-1 — what the viewer shows, and the fix.
A WMS that works in QGIS and fails in your web map is almost never broken. Mixed content, CORS, a user-agent rule, a GetCapabilities that answers with HTML, a WMTS URL in the WMS box: the short list of real causes, each with the symptom you see and the fix that works.
Forty-eight URLs across sixteen elevation sources, probed on 11 September 2026: what each one answered, what resolution and vertical datum it really carries, which ones a browser app can read, and which famous links are now dead.
SIRGAS 2000, SAD69, Corrego Alegre, MAGNA-SIRGAS, POSGAR 2007 — every code here was read out of GDAL 3.13.3 on 11 September 2026, not from memory. Which UTM zone covers which Brazilian state, why a distance measured in EPSG:3857 runs 9% long at São Paulo, and how to convert.