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OnTheMap is the U.S. Census Bureau’s web tool for mapping where people work and where workers live, labelled on its own site “Workforce & Commuting Data Maps.” This page is for researchers who need to decide whether to use the mapping interface or the underlying LODES files, cite the data correctly and understand its limits (sources read 2026-11-07).
What OnTheMap is
OnTheMap is an interactive mapping and reporting application run by the Center for Economic Studies at the U.S. Census Bureau as part of the Longitudinal Employer-Household Dynamics (LEHD) program. Its credit line reads “U.S. Census Bureau, Center for Economic Studies, LEHD.” The tool is built on LEHD Origin-Destination Employment Statistics (LODES), the same data the Census Bureau publishes as downloadable files. The Census Bureau also lists a separate “OnTheMap for Emergency Management” application alongside it.
Who runs it and what the data cover
The Census Bureau’s LEHD pages describe LODES as state-based data with three file types, all at census-block detail and available for “most states”:
- OD (Origin-Destination): jobs linked between a home block and a workplace block.
- RAC (Residence Area Characteristics): jobs counted by where workers live.
- WAC (Workplace Area Characteristics): jobs counted by where the workplace is.
LODES is built from “tabulated and modeled administrative data,” so it is not a survey sample and is subject to nonsampling error. The LEHD pages state which census-block vintage each version uses: LODES version 8 uses 2020 census blocks, LODES7 uses 2010 blocks and LODES5 uses 2000 blocks. The vintage of a particular series is recorded in the “version” text file shipped with it.
How to use it
The Census Bureau’s LEHD help hub links to “Start OnTheMap,” “Help,” and “Download LODES Data”; those are the entry points. From the OnTheMap start page, the documented ways to bring your own geography or earlier work into the tool are:
- Import a KML file.
- Import a Shapefile (ZIP/SHP); a projection must be supplied through a PRJ file or an EPSG code.
- Open a saved .OTM file.
- Open a file saved from a previous LODES vintage; the page warns that “results may have changed” when a file is reloaded against newer data.
The start page also links to Help and Documentation, a text-only version and a feedback address ([email protected]). For the current menu names and step-by-step analysis workflow, use the “Help and Documentation” link on the application itself and the Census Academy OnTheMap training, because the interface is revised with each data release.
Which to use: OnTheMap or LODES files
The mapping tool suits exploring an area, drawing a custom boundary and producing a quick profile. Download the LODES files when you need the full block-level tables for modelling, merging with other geographies or reproducing a result. Reproducibility is the practical reason: a saved .OTM file can produce different results after a data vintage change, whereas a downloaded file with its “version” text file is a fixed, citable object. Record which vintage you used in either case.
Confidentiality
The OnTheMap start page states that the product was reviewed for unauthorized disclosure and approved (disclosure review number CBDRB-FY21-249). The LEHD pages state that the confidential underlying microdata are accessible only for approved projects through the Federal Statistical Research Data Centers. Public LODES and OnTheMap outputs are therefore the route for most researchers; the microdata route requires an approved project.
How to cite LODES
The LEHD data page gives this format: U.S. Census Bureau, “{File Name},” LEHD Origin-Destination Employment Statistics, {Vintage}, {LODES URL}, accessed on {Date}. Take the vintage from the “version” text file in the series you downloaded. Files are published at lehd.ces.census.gov/data/lodes/. For OnTheMap outputs, include the tool name, the credit line above and the access date. See also the CASRAI entries on the data citation principle, repository citation and open data.
Strengths and limits
| Strength | Limit |
|---|---|
| Block-level detail from administrative records, not a sample | Tabulated and modeled administrative data; subject to nonsampling error |
| Same data available as downloadable OD, RAC and WAC files | Coverage is “most states,” not all |
| Custom areas via KML or Shapefile import | Saved files reloaded on a newer vintage may give changed results |
| Disclosure-reviewed public outputs | Confidential microdata only for approved projects at Federal Statistical Research Data Centers |
Block vintages also differ between versions (2000, 2010, 2020 blocks), so comparing results across LODES versions needs care.
Alternatives
| Option | What it is (per Census Bureau LEHD pages) | Best when |
|---|---|---|
| OnTheMap | Web mapping and reporting on LODES | You want to explore or profile an area visually |
| LODES files (OD, RAC, WAC) | State-based block-level downloads at lehd.ces.census.gov/data/lodes/ | You need tabular data for analysis or replication |
| Restricted microdata | Confidential data via Federal Statistical Research Data Centers, approved projects only | Public outputs cannot answer an approved research question |
If you deposit derived tables or maps, a data repository is where they belong, or a sensitive-data repository if disclosure limits apply.
FAQ
What is OnTheMap?
It is the U.S. Census Bureau’s Workforce and Commuting Data Maps tool, run by the Center for Economic Studies within the LEHD program and drawing on LODES data.
What is the difference between OnTheMap and LODES?
LODES is the data (OD, RAC and WAC files at census-block level); OnTheMap is the interactive application that presents it.
Which census blocks does LODES use?
Version 8 uses 2020 blocks, LODES7 uses 2010 blocks and LODES5 uses 2000 blocks.
Can I use my own boundary?
The tool accepts KML and Shapefile imports; Shapefiles need a projection supplied by a PRJ file or EPSG code.
Can I get the confidential microdata?
Only for approved projects through Federal Statistical Research Data Centers.
Sources
- U.S. Census Bureau, OnTheMap start page, onthemap.ces.census.gov (read 2026-11-07).
- U.S. Census Bureau, LEHD Origin-Destination Employment Statistics (LODES) data page, lehd.ces.census.gov/data/ (read 2026-11-07).
- U.S. Census Bureau, LEHD OnTheMap help hub, lehd.ces.census.gov/applications/help/onthemap.html (read 2026-11-07).
