How to Batch Convert Many GIS Files at Once

One file at a time is fine for one file. Then a project lands with 40 Shapefiles, a folder per county, or a partner who sends data each week. At that point, one-by-one work stops being careful and starts being the risk: the file you rush at 5 p.m. is the one that ships with the wrong target format.

Batch conversion means you set the rules once — output format, coordinate system, checks — and run many files through the same rules. Done well, it is both faster and safer than hand work, because the rules cannot drift from file to file. This guide shows you how to use the batch converter on the home page in a way that stays safe.

The worked example is a state data drop: 24 county files that must all become GeoJSON in WGS 84 for a web map. The same method fits any mix this site reads: Shapefile, GeoJSON, KML, GeoPackage, GML, CSV, and GPX.

What Makes a Batch a Batch

A batch is not just a pile of files. It is a pile of files that share one job: the same output format, the same target coordinate system, and the same checks at the end. If half your files need GeoJSON and half need KML, that is two batches, not one. Splitting by job is what lets you set the rules once and trust them for every file in the run.

Files in a batch should also share a shape of data. County files from one state drop are ideal: same fields, same source system, same quirks. A mixed pile — surveys, GPS tracks, and office exports in one run — hides faults, because no single check fits all of them. Sort first, batch second. The sorting is the skilled part; the running is the easy part.

Each file in a batch counts as one conversion. On the Free plan you convert one file at a time, 5 a month. Starter runs batches of up to 10 files, 200 conversions a month. Pro runs batches of up to 25 files, 1,000 conversions a month, with API access so a weekly drop can run on a schedule with no clicks at all.

The Two Ways Batches Go Wrong

The first way is a bad rule applied 24 times. A wrong target system in a single job ruins one file. In a batch, it ruins the whole drop, in a neat, uniform way that looks like success. That is why this guide spends a full step on a test file. Run one file through the batch rules, check it hard, and only then run the rest. The test is not a delay. It is the job.

The second way is one bad file in a good pile. A county file with a missing .dbf, a CSV with swapped columns, a KML with a broken tag. If the batch stops dead at file 13, you lose the run. If it skips the file in silence, you lose the county. The sound behavior — and the one this site follows — is to convert what converts, name what failed, and say why, so your checklist at the end has one clear line to chase.

Both failure modes have the same cure: a manifest. That is just a list — files sent, files converted, counts per file, failures named. Keep the manifest with the output. When a partner asks, three months later, whether the north county was in the March drop, the manifest answers in seconds. Memory does not.

Words to Know

Batch work adds one word of its own — the manifest, a list of what ran and what each run produced. The text defines it as it goes.

• Layer. one set of features of one kind, shown as one sheet on a map. A city file may hold a roads layer and a parks layer.
• Feature. one real thing on the map, such as one park, one road, or one shop. A file can hold many features.
• Bounding box. the smallest box that holds all your data. It is named by its west, south, east, and north edges. A box in the wrong place is a fast sign that a file went wrong.
• ZIP file. one packed file that holds many files in it. A Shapefile needs a ZIP, since a Shapefile is three or more files that must travel as one set.

When Batch Conversion Pays

Batch work pays when the pile shares one job and the job will come again. The clear signs:

• You hold 10 or more files that need the same output format and system.
• A partner sends the same drop each week or month, in the same shape.
• A project must move as a whole: all counties, all zones, all survey sheets.
• You catch yourself doing the same clicks for the third file in a row.

It does not pay for three files with three different jobs. Convert those by hand and spend the saved setup time on checks. And if the pile is one file repeated — the same export in 20 ZIPs — dedupe first. There is no prize for converting the same data 20 times. For the single-file method in full, the single-file Shapefile to GeoJSON steps are the base this guide builds on.

A Worked Example: 24 County Files

A state office drops 24 county Shapefile ZIPs. All must become GeoJSON in WGS 84. The source system is one state plane system for all 24. Here is the run, as the manifest records it:

Note the test file choice: the largest county, not the smallest. A big file shows faults a small one hides — long field values, edge shapes at the county line, a slow run time you can plan around. If the largest file passes the hard check, the other 23 are very likely clean under the same rules.

Note also the flag. One flagged file in 24 is a normal drop, not a failed job. The batch did its work: 23 files converted under proved rules, and the one bad file named with its cause — a missing .dbf part — while the facts were fresh. That county was fixed the next day with the repair steps in our Shapefile repair guide, and converted under the same rules.

Keep Your Source Safe

Work on a copy, not on your only file. Save the first file in a safe place and do not change it. If a test goes wrong, you can start again from the clean source. This sounds like a small point, but it saves more work than any other habit in this guide.

Give each test a clear name. A name like test-1 tells you the order of your tries. A name like final-final-2 tells you nothing at all. When you find the settings that work, write them down in a short note next to the files. The next file of the same kind will then take minutes, not an hour.

How to Batch Convert GIS Files, Step by Step

Sort, test, run, reconcile. The middle step is the shortest. Keep it that way: the work is in the sorting and the reconciling, and that is where quality lives.

Step 1: Sort the pile by job

Make one folder per batch: same output format, same target system, same kind of data. Move anything that does not fit into a second folder for a second run. Check each Shapefile is a ZIP with its full set of parts. A sort that takes 15 minutes here saves a failed run and a vague afternoon later.

Step 2: Write the manifest before you run

List each file in a note or a sheet: file name, source count if the sender gave one, and a blank column for the output count. This list is your contract for the run. If a sender gives no counts, your output counts become the record — still write them down per file, not just as a grand total.

Step 3: Run one test file through the batch rules

Pick the largest or most complex file. Run it alone with the exact settings the batch will use: output format, target system, field choices. Then check it hard — counts, field names, preview place, one known town or bridge by hand. Do not proceed on a shrug. If the test file has a fault, the batch has a fault, 24 times over.

Step 4: Load the batch and set the shared rules

On a paid plan, add the files to one batch job — up to 10 files on Starter, up to 25 on Pro — and set the output format and target system once for the run. For piles bigger than one batch, split them into groups that match the manifest order, so results come back in an order you can reconcile without sorting by hand.

Step 5: Run the batch and let it finish

Start the run and wait for the full report. Big files take minutes, not seconds; a batch of large county files is a coffee, not a click. If email alerts are on for your plan, you will get a note when the batch is ready, with the download link kept for 72 hours. Do not start a second run over the first with changed rules to 'save time'. Two rule sets in one drop is how manifests stop matching.

Step 6: Reconcile the results against the manifest

Go file by file down your list. Tick each output count against its line. Read every flag. A flag is not a failure of the batch; an unexamined flag is a failure of the process. For each flagged file, note the cause and the fix owner: you, with a repair, or the sender, with a re-send.

Step 7: Pack and hand over the batch as a unit

Download the results and keep them in one folder with the manifest and a one-line note: source, rules used, date, and the flags and their state. Name the folder for the drop, like state-counties-geojson-2026-11-07. When you pack each result as a GeoPackage for tidy hand-over instead of GeoJSON, the same manifest habit applies — one master folder, one list, no loose files with proud names and no history.

How to Check Your Result

Never trust a conversion you have not checked. The good news is that a sound check takes just a few minutes, and it is the same each time you work on a batch conversion.

First, match the counts. The report shows how many features went in and how many came out. The two counts should be the same. If the output count is lower, a step dropped data, and you should find out why before you share the file.

Next, look at the map preview. Your data should sit in the right town, state, or sea. If it sits in the ocean, or on the wrong side of the world, the coordinate system is the prime suspect. Zoom in on one place you know well and check that roads, parks, or points fall where they should.

Then check the fields. Open the field list in the report and read the names. Make sure the key fields are still there, with the right names and the right kind of values. Pick one feature you know and match each value back to the source by hand.

• Spot-check the first, middle, and last files in the run with a map preview. Rule drift and sorting slips show at the seams.
• Add the output counts and compare the total to the sum of the sender's counts, if they gave them. A total can hide one empty file and one doubled file; per-file checks cannot.
• Add CSV point files to the pile the same way: add CSV point files to the same batch once each CSV has the same column names for longitude and latitude.

Last, keep the source file. Save the result with a clear name that holds the date and the format, like parks-geojson-2026-11-07.zip. Keep the source and the result in one folder. If a question comes up next month, you can trace each feature back to where it came from.

Common Mistakes and How to Fix Them

One File Failed and the Rest Look Fine, So You Ship

Do not ship a silent gap. A missing county in a state map is the kind of fault a reader finds in a public meeting. Hold the hand-over until the flagged file is fixed, or ship with the gap named in the note in plain words, so the reader decides with open eyes.

All Outputs Sit in the Wrong Place

The shared rule was wrong — most often the target system, or a source system assumed for all files when one sender used a different one. This is why the test file matters. If it happens anyway, fix the rule, rerun the whole batch under one rule set, and replace the outputs as a unit. Never patch single files out of a batch.

Counts Match in Total but Not per File

Totals lie. One file converted twice and one not at all can sum to the right number. Always reconcile per file, by name. If your results came back sorted in a different order than your manifest, sort both lists by file name before you compare, or you will chase ghosts.

Field Names Differ Across the Outputs

The sources differed — one county used road_name, the next used name_road. A batch applies one rule set, but it cannot invent a shared schema. If the outputs must join into one layer, fix the schema at the source or map the fields per file before the batch, and note the mapping in the manifest.

The Run Took Far Longer Than Expected

One huge file can dominate a batch. Check file sizes at the sort step and run the giant alone, or first, so the rest of the pile is not held behind it. For files past the plan size limit — 500 MB on Starter, 5 GB on Pro — split the data by area at the source, or step up a plan for the month of the big job.

What the Plans Allow

You can start free. The Free plan gives you 5 conversions a month, with one file at a time and a size limit of 25 MB per file. That is enough to test a 24-county data drop on real data and check the result with care.

Starter costs $9 a month. It gives you 200 conversions a month, files up to 500 MB, and batch jobs of up to 10 files at once. Pro costs $19 a month. It gives you 1,000 conversions a month, files up to 5 GB, batch jobs of up to 25 files, and API access for work you run on a schedule. You can compare batch sizes across plans before you pick.

All plans work the same way at the core. You get a map preview, feature counts in and out, and a clear report if a file has a fault. Your files are kept for 72 hours so you can download them again, and then they are deleted.

Frequently Asked Questions

How many files can I convert in one batch?

Up to 10 files at once on Starter ($9 a month, 200 conversions a month) and up to 25 at once on Pro ($19 a month, 1,000 conversions a month). Each file in a batch counts as one conversion. The Free plan converts one file at a time.

Can one batch hold different input formats?

The files in a run should share a job and a data shape. A pile of Shapefile ZIPs is a clean batch. Mixing in a CSV with different column names or a KML with hand styles invites faults the shared rules cannot fit. Sort by kind first; run more batches, each one clean.

Can a weekly drop run itself?

On Pro, yes: API access lets your own script or schedule send the files and fetch the results with the same rule set each week. Keep the manifest habit even then — have the script log per-file counts and flags, and read the log. Automation moves the work; it does not remove the check.

What if one file in the batch is corrupt?

The run converts the sound files and flags the bad one by name, with the cause where the tool can name it. Fix or re-request that file, run it alone under the same rules, and add its line to the manifest. The batch record then shows the full, true history of the drop.

Should I ZIP the outputs together to send on?

Keep the batch folder as the unit: outputs, manifest, and note. ZIP the folder if your send method needs one file. What you must not do is send the outputs loose with no manifest. The list is part of the data. It is how the next person proves the drop is whole.

Final Checklist

Run through this short list before you share your file:

• The pile was sorted by job before the run: one format, one system, one data shape.
• A test file passed the hard check under the batch rules.
• Every file is reconciled by name and count in the manifest.
• Every flag has a cause and an owner, in writing.
• The hand-over folder holds outputs, manifest, and a dated note.

If each point passes, your file is ready to use.

References

• https://www.data.gov/ — Data.gov, the U.S. government open data home, a common source of multi-file GIS drops that need batch work.
• https://www.usgs.gov/programs/national-geospatial-program/national-map — The USGS National Map program page, on national geospatial layers maintained and shipped at scale.
• https://www.census.gov/geographies/mapping-files/time-series/geo/tiger-line-file.html — The Census Bureau TIGER/Line Shapefiles page; its per-county files are a classic batch conversion job.