FlowForge

Free Bulk File Renamer and Four Workflow Tools

Rename hundreds of files step by step and see every new name first, clean CSV and Excel tables with steps you can run again, tidy email lists, turn example data into JSON Schema and types, and build forms, with nothing uploaded.

Help guideFAQ

What you open, type or paste stays in this browser. Press 1 to 5 to switch tools and ? for help.

How to Use FlowForge

1

Add files or names

Choose a folder, add files or drop them on the page, or type a list of names. Only the names, sizes and dates are read, on your device, until you rename.

2

Build the new names

Add steps such as Replace text, Remove copy marks, Number or New name from a pattern, or start from a ready-made set. Each step says how many names it changed.

3

Check, then rename

Every new name is shown beside the old one, with clashes and names Windows does not allow marked. Rename in the folder (with Undo), download a zip or take a script that asks first.

4

Clean a table

In Tables, open a CSV or Excel file or paste cells, click a column name or add steps, and save the steps as a recipe for next month's file.

5

Tidy an email list

In Email lists, paste addresses in any form. Typos are fixed and shown, repeats and addresses that cannot work are taken out, and the clean list is ready to copy.

6

Make types and forms

In Schema and types, paste example data or a list of fields to get a JSON Schema, TypeScript, Zod and Pydantic. Forms turns the same fields into a form you can try and save.

Why Use This Bulk File Renamer?

👀 Every new name shown first

Old and new names sit side by side with what was removed and what was added, and the list says which names would clash, are too long or will not work on Windows.

↩️ Undo, or a script that asks

Renaming in the folder can be undone straight away; swaps and changes of capital letters go through a temporary name, and a script lists every rename and waits for YES.

🔁 Steps you can run again

Rename steps and table clean-ups are saved as sets and recipes, so next month's photos or export are done in a click, with each step saying what it changed.

📅 Dates and numbers read as people write them

03/04/2025, 5 Jan 2025 and Excel's own dates become one format; 1,23,456 and 1.234,56 become plain numbers; phone numbers get one style.

🧾 One source, four outputs

The same fields give a JSON Schema, TypeScript, Zod and Pydantic, and the same schema becomes a form, so the shapes never drift apart.

🔒 Nothing uploaded

There is no account and no upload. Files, tables, lists and answers are worked on in your browser, and what you keep stays in this browser.

Renaming, Cleaning and Schemas Explained

🔀 Why swaps need a temporary name

Renaming a.jpg to b.jpg while another file is already called b.jpg would overwrite it or fail, and Windows and Mac treat A.JPG and a.jpg as the same file. When one new name is another file's old name, or only the capital letters change, FlowForge first gives the file a temporary name, then the final one, so no file is ever overwritten.

🧹 Steps instead of formulas

A spreadsheet clean-up usually means helper columns full of formulas. Here each change is a step in a list: split this column, write those dates as 2025-01-31, remove rows without an email. Click a step's number to see the table at that point, switch a step off to compare, and save the list to run on the next file.

📐 What a JSON Schema is

A JSON Schema describes the shape of data: which fields a record has, which are required, and what each may hold, such as an email, a date or a number from 18 to 120. Programs use it to check data before they trust it; TypeScript, Zod and Pydantic are the same description written for the code that reads the data.

Frequently Asked Questions

How does the bulk file renamer work?

Choose a folder, add files or type a list of names, then add steps: replace text, add text, remove copy marks such as (1), change case, number the files, build a new name from a pattern such as the date a photo was taken, tidy up spaces and accents, or change the extension. Each step works on the name the step above it made, and every new name is shown next to the old one, with what was taken out and what was added, before anything changes.

Will it rename the files on my computer?

Only when you ask. In Chrome and Edge on a computer, with a chosen folder, Rename in the folder renames the files themselves after you confirm, and Undo puts the old names back straight afterwards. In other browsers you can download renamed copies as a zip, or get a script for PowerShell, the Command Prompt or Mac and Linux that lists every rename and changes nothing until you type YES. Names that would clash, are too long or that Windows does not allow are marked first and left as they are.

Are my files, tables or lists uploaded?

No. Files, tables, email lists, example data and form answers are read and worked on by your browser on this device, and they are not sent anywhere. Your steps, recipes and settings are kept in this browser for next time, and the open table, texts and answers in its own storage until you clear them.

What can the Tables tool do with a CSV or Excel file?

Split and join columns, build a column from a pattern, rename, remove and move columns, clean spaces, change case, find and replace, pull out an email, domain or number, fill empty cells from above, write dates and numbers one way, clean phone numbers, keep or remove rows, remove duplicates, sort, look up columns from a second table and add its rows. Steps can be saved as a recipe and run again on next month's file, and the result saved as CSV, Excel, JSON, Markdown, HTML or SQL, or split into one file per value or per so many rows.

How does the email list cleaner check addresses?

It reads the written address only, on this device: whether it has one @, a name part and a domain, no spaces or characters that are not allowed, and a real domain ending from the official list. Likely typos such as gmial.com are fixed and shown, repeats are removed, and throwaway or shared addresses can be left out. It does not contact any mail server, so it cannot tell whether a mailbox exists.

What do I get from Schema and types?

Paste example JSON, JSON Lines, a CSV, an existing JSON Schema or a plain list of fields such as email*: email. You get a JSON Schema (2020-12 or draft 7), TypeScript interfaces, a Zod schema and Pydantic models from the same source, a check of any data against the schema with the place of each problem, and made-up example records for tests.

How is it different from the site's other tools?

ToolForge finds duplicate files and lists them in a rename script, but does not build new names step by step; its Text to table and Table to CSV, DataForge and CodeForge change tables and data from one format to another, while the Tables tool here changes the table itself with steps you can run again. Nothing else on the site cleans email lists, makes JSON Schema and types from examples or builds forms.

How FlowForge works

Five tools for the small jobs that eat an afternoon. Everything you open, paste or type stays in this browser on this device; nothing is uploaded. Your steps, recipes and settings are kept in this browser for next time. The tools pass work to each other: a table can become a schema or a form, a column of emails goes to the email cleaner, form answers open as a table.

Rename files

Choose a folder (or drop one here), add files, or type names. Then add steps: replace text, add text, remove copy marks like (1), change case, number them, build a new name from a pattern such as {taken:YYYY-MM-DD} {n:3} (the date a photo was taken, read from the photo itself), tidy up, change the extension. Each step works on the name the step above it made, and says how many names it changed. Every new name is shown with what was removed and what was added, and names that would clash, are too long, or that Windows does not allow are marked before anything happens. Click the pencil to type one name yourself.

In Chrome and Edge, with a chosen folder, Rename in the folder renames the files themselves, and Undo puts the old names back. Swaps (a to b and b to a) and changes of capital letters go through a temporary name, so no file is ever overwritten. Elsewhere, download renamed copies as a zip, or get a script for PowerShell, Command Prompt or Mac and Linux, with an undo script too. A script lists every rename and changes nothing until you type YES; a Windows script leaves out names Windows does not allow.

Tables

Open CSV, TSV, Excel (.xlsx, any sheet), JSON or Markdown, or paste cells from Excel or Google Sheets. Click a column name for what you can do with it, or add steps on the left: split a column (at a separator, into first, middle and last name, or into rows), join columns, build a column from a pattern, rename, remove and move columns, clean up spaces, change case, find and replace, pull out an email, domain or number, fill empty cells from above, format dates written any way, clean numbers (including 1,23,456 and 1.234,56), clean phone numbers, keep or remove rows, remove duplicates, sort, look up columns from a second table (like VLOOKUP) and add the rows of another file. Click a step's number to see the table at that point, with changed cells marked. Save the steps as a recipe and run it on next month's file. Save the result as CSV, Excel, JSON, Markdown, HTML or SQL, or split it into one file per value or per so many rows.

Email lists

Addresses are found in any text: Name <address> forms, commas and semicolons, a spreadsheet column (the name columns come along), a contacts file, or an address written as name [at] example [dot] com. Each one is checked on this device, with the reason when it cannot work: a missing domain, a space, a domain ending that does not exist (IANA's list of 1,436 endings, as of 12 November 2026, is built in). Only the written address is checked: no mail server is asked, so a mailbox that does not exist is not found. Likely typos such as gmial.com or .con are fixed and shown, and each fix can be undone. Repeats are removed, and with Also the same person, a.sha@gmail.com and asha+news@gmail.com count as one. Throwaway services and shared addresses like info@ can be left out, and a do-not-send list removes people who unsubscribed. Copy the clean list in the form your email program wants, or in groups for sending in batches.

Schema and types

Paste one example record or many (JSON, JSON Lines or a CSV), and FlowForge learns the fields from all of them: which are always there, which can be empty, which hold dates, emails, links or IDs, and which have only a few values. Or write the fields in plain words, one per line: email*: email, age: whole number 18-120, plan: one of free, pro, team, tags: list of text; a star means required, and indented lines belong to the field above. You get a JSON Schema (2020-12 or draft 7), TypeScript interfaces, a Zod schema and Pydantic models. Paste data under Check data to see exactly where it does not fit. Example data makes realistic records that fit the schema.

Forms

Start from an example or an empty form, then add fields: text, long text, email, phone, number, date, yes or no, choose one, choose several, rating, lists, groups and repeating groups. Each field can have help text, an example, limits and a pattern. The form on the right works as you build it: fill it in and press the button to save an answer; answers collect into a table you can download as CSV, Excel or JSON. Save as a web page gives one HTML file that checks answers by itself and either shows them, sends them to an https address of your own, or opens an email to you.

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