Local datafile viewer and analyzer · macOS

Inspect dataset files.Understand data quality.Right on your computer.

Splitline is a local datafile viewer and analyzer for Mac, built for easy dataset-file inspection directly on your computer. Understand structure, schema, coverage, drift, and parse issues without uploading the source. JSON documents stay view-only; complete row datasets can be repaired. Optional AI is request-only, and validated plans execute locally.

  • Dataset inspection, made easy
  • Explainable quality checks
  • Files stay on your Mac
  • Lifetime license, never a subscription
  • Coming soon for macOS
JSONdocumentsJSONLrow dataCSVrow dataTSVrow data

01 / Two jobs, one tool

Opening a file should reveal more than syntax.

Splitline opens the data in its natural shape, then shows structure, field coverage, parse issues, mixed types, and cross-file drift. Every warning keeps the row, file, or field evidence close enough to verify.

“A quality warning is useful only when you can reach the evidence behind it.”

02 / How it works

From file to confidence,
without the detour.

Open one file or a whole folder. Splitline selects the right workspace, shows whether a row dataset needs attention, and keeps every normal inspection step offline.

  1. 01

    Open the file directly.

    Double-click in Finder, drop a folder, or choose JSON, JSONL, CSV, and TSV directly.

    Nothing to import. Nothing to upload.
  2. 02

    Inspect data quality.

    Profile types, coverage, cardinality, ranges, common values, parse issues, and split-to-split drift.

    Every warning keeps its evidence visible.
  3. 03

    Repair the rows that need it.

    Edit primitive and nested values, delete a bad row, undo, and save without reformatting untouched lines.

    Your source stays recognizable.

03 / The workspace

Open quickly.
Inspect deeply.

Splitline opens each supported format without an import step. In row datasets, the table, field profile, issues, and selected record stay together, so a quality finding never loses its source context.

Splitline · assistant-quality-demo
Splitline Rows view showing a selected data record beside its row inspector
Rows Search nested values, scan content-sized columns, edit cells, and keep the full record open beside the table. Inspect 1:1

04 / Data quality + analysis

Check the quality.
Then ask deeper questions.

Health Check inspects loaded row files automatically and points each deduction back to evidence. Analyze is optional and stays idle until you open the chat and send a request; the outbound and local parts remain visibly separate.

Health check On-device · automatic

A quality score.
Evidence for every deduction.

Splitline checks parsing integrity, cross-split schema drift, mixed field types, and empty files. Every deduction stays paired with issue details and the file or field evidence behind it.

  • Runs as soon as files parse
  • Explains every deduction
  • Keeps source evidence visible
Example health check3 files · 12 rows
82Dataset health

2 checks need review.
The rest of the dataset is ready to inspect.

  • Parsing integrityReview1 malformed record
  • Split consistencyReview1 field changed type
  • File readinessPass0 empty files

AI chat analysis By request only · user initiated

Your question
starts the path.

Nothing analyzes your rows in the background. Open Analyze, review the composer’s send boundary, and submit a question. The model may answer in prose or propose a narrow plan—never code to execute.

  1. 01 Open Analyze
  2. 02 Review boundary
  3. 03 Ask in chat
  4. 04 Validate reply
  5. 05 Run locally
  6. 06 Inspect result

Only a validated analysis plan reaches Splitline’s local execution engine. By default, row values remain excluded; bounded samples are a separate, explicit choice.

Read the local AI analysis guide
Analyze chat By request only
Next requestNothing sent until Submit

Will sendTask · dataset and file name · split · row count · field profiles

ExcludedSource file · row values

You

Compare average quality score by task.

Validated planAllowed operations only
Group
task
Measure
average · quality_score
View
bar chart · descending
classification0.99
summarization0.97
procedure0.96

✓ Plan checked8 rows executed locally

05 / Built for the odd parts

Data rarely arrives clean.
Splitline expects that.

01

Navigate deep JSON without mounting the whole universe.

Breadcrumbs, branch history, bounded array ranges, search scopes, and a foldable Raw view keep large documents explorable.

Explore JSON files on Mac
02

Repair the record without rewriting everything around it.

Patch-based edits change only the rows you touched. Untouched source lines stay byte-identical, so a small fix does not turn into an unreadable whole-file diff.

Edit JSONL, CSV, and TSV safely
03

Keep row-shaped data in one consistent workspace.

JSONL, CSV, and TSV share the same profiling, schema, drift, table, edit, and Analyze surfaces. Change formats without relearning the tool.

Profile row datasets

06 / Local first

The shortest data path
is no path at all.

Normal file inspection makes no network request. Parsing, profiling, search, edits, and local analysis happen on your Mac. The packaged app may check GitHub for a newer signed release, sending no app-specific data beyond its version; downloads remain user initiated.

Read the privacy boundary

Ready for the next file

Open the next file.
Know what you have.

Splitline has not launched yet · one message when it does

Join the waitlist Universal DMG · macOS 12+ · signed and notarized

Product screenshot · full resolution