Convert Plain Text to Protobuf Schema Online

Paste a Plain Text table below, edit it if you need to, and get Protobuf Schema back. The conversion runs in your browser, so nothing is uploaded, there is no size limit and there is no signup.

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Nothing here is uploaded. The parsing happens on this page.
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The output will appear here once there is a table to convert.

What Plain Text is

Plain text here means columns lined up with spaces, the way a command line tool prints a table.

Terminal output, log files, fixed-width exports from older systems.

What Protobuf Schema is

A proto3 message definition with numbered fields.

gRPC services and anything using Protocol Buffers.

What changes when you convert Plain Text to Protobuf Schema

Two shapes are handled. If the same character positions are blank on every line, those gutters are treated as column boundaries, so values containing single spaces stay intact. Otherwise the lines are split on runs of whitespace.

Field numbers are assigned in column order starting at one. Types are inferred from the values.

What carries over from Plain Text to Protobuf Schema

One property of the plain text has no home in Protocol Buffers, and it is worth knowing which before you convert.

Protocol Buffers wants a type for each column, and plain text does not record one, so each column is typed from what its values look like. A column of digits that should stay text - a zip code, a phone number, a leading-zero id - is the usual thing to check afterwards.

Protocol Buffers has no header row. The column names are repeated as keys on every record instead, which is why the result is bigger on disk than the table it came from.

A worked example

Three rows of staff data, with an identifier that has a leading zero, a value containing a comma, a value containing quotes and one blank cell. Those are the four places formats disagree, so they are the four places to look.

Plain Text in
id   name              role           started     hours
007  Halima Yusuf      Analyst, data  2024-03-15  38.5
012  Jonah "Jo" Pryce  Engineer       2025-11-02
104  Wei Chen          Manager        2023-06-30  40
Protobuf Schema out
syntax = "proto3";

message staff {
  int64 id = 1;
  string name = 2;
  string role = 3;
  string started = 4;
  double hours = 5;
}

Questions

How do I convert Plain Text to Protobuf Schema?

Paste your Plain Text into the box above or drop the file onto it. Check the table in the grid, then copy or download the Protobuf Schema from the output panel. It takes one step and the data never leaves your browser.

Is there a limit on file size?

No. The work happens on your own machine, so the limit is your machine's memory rather than an upload cap. A file with tens of thousands of rows converts in a second or two.

Is my data uploaded anywhere?

No. The parsing and generating are done by JavaScript running on this page. You can watch the network tab while you convert and see that nothing is sent.

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