JSON Tools

JSON to CSV

Convert JSON files to CSV format directly in your browser. No upload required — your data never leaves your device.

JSON to Parquet

Convert JSON files to Parquet format directly in your browser. No upload required — your data never leaves your device.

JSON to TSV

Convert JSON files to TSV format directly in your browser. No upload required — your data never leaves your device.

JSON to NDJSON

Convert JSON files to NDJSON format directly in your browser. No upload required — your data never leaves your device.

JSON to Arrow

Convert JSON files to Arrow format directly in your browser. No upload required — your data never leaves your device.

JSON to Excel

Convert JSON files to Excel format directly in your browser. No upload required — your data never leaves your device.

JSON to YAML

Convert JSON files to YAML directly in your browser. Download clean, human-readable YAML — no upload required.

JSON to XML

Convert JSON files to XML directly in your browser. Download a structured XML document with one element per row — no upload required.

JSON to SQL

Convert JSON files to SQL INSERT statements directly in your browser. Copy or download the generated SQL — no upload required.

JSON to Markdown

Convert JSON files to a Markdown table directly in your browser. Copy the output and paste it into any Markdown document.

JSON to HTML

Convert JSON files to an HTML table directly in your browser. Copy the markup or download a ready-to-use HTML file.

CSV to JSON

Convert CSV files to JSON format directly in your browser. No upload required — your data never leaves your device.

Parquet to JSON

Convert Parquet files to JSON format directly in your browser. No upload required — your data never leaves your device.

NDJSON to JSON

Convert NDJSON files to JSON format directly in your browser. No upload required — your data never leaves your device.

TSV to JSON

Convert TSV files to JSON format directly in your browser. No upload required — your data never leaves your device.

Arrow to JSON

Convert Arrow files to JSON format directly in your browser. No upload required — your data never leaves your device.

Excel to JSON

Convert Excel files to JSON format directly in your browser. No upload required — your data never leaves your device.

YAML to JSON

Convert YAML files to JSON format directly in your browser. No upload required — your data never leaves your device.

JSON Viewer Online

View and inspect JSON files directly in your browser. Browse rows, check column names and data types — no upload required, your data stays on your device.

JSON Beautifier

Format and indent JSON so it is readable.

JSON Minifier

Remove whitespace from JSON to shrink it.

JSON Schema Validator

Validate JSON against a JSON Schema.

JSON Diff

Compare two JSON documents and highlight the differences.

JSONPath Tester

Test JSONPath expressions against JSON data.

SQL Query Tool

Load one or more files and query them with SQL. Each file becomes a table.

Remove duplicates

Remove duplicate rows from JSON files instantly in your browser. No upload, no server — 100% private.

Fuzzy deduplicate

Find near-duplicate rows in JSON files using Levenshtein edit distance or Jaro-Winkler similarity — all in your browser. Set your own threshold and download the matched pairs as CSV — no upload required.

Trim

Trim leading and trailing whitespace from all text columns in JSON files, directly in your browser. No upload required.

Fill empty values

Fill empty and null values in JSON files with a custom replacement value, directly in your browser.

Coalesce columns

Fill null values in JSON files from other columns — return the first non-null value across up to 8 columns in priority order. Add the result as a new column. Runs entirely in your browser.

Find & replace

Find and replace text values in JSON files directly in your browser. Supports plain text and regex patterns across any column — no upload required.

Convert case

Convert text columns to UPPERCASE, lowercase, or Title Case in JSON files directly in your browser. Apply case conversion to any or all text columns at once — no upload required.

Change column types

Change column data types in JSON files directly in your browser. Cast text to numbers, dates to timestamps, or any supported type conversion — no upload required.

Convert encoding

Detect and convert the character encoding of JSON files directly in your browser. Switch between UTF-8, Latin-1, Windows-1252, and more — no upload required.

Validate emails

Validate email addresses in JSON files directly in your browser. Add a boolean column flagging valid and invalid emails, or filter to show only invalid rows — no upload required.

Validate structure

Validate JSON file structure in your browser. Check null counts, distinct values, and data types for every column — no upload required.

Filter

Filter rows in JSON files by column value, directly in your browser. Your data stays on your device.

Filter by date range

Filter JSON files to rows within a date range using simple start and end date pickers. See a live match count before you apply the filter — no upload required, runs in your browser.

Search text

Search for text across all string columns in JSON files directly in your browser. Filter rows to only those containing your search term and download the results — no upload required.

Select columns

Drop or select specific columns from JSON files directly in your browser. No upload required.

First N rows

Extract the first N rows from JSON files directly in your browser. Choose how many rows to keep and download the result — no upload required.

Last N rows

Extract the last N rows from JSON files directly in your browser. Choose how many rows to keep and download the result — no upload required.

Sample

Sample rows from JSON files — first N, last N, or random — directly in your browser.

Shuffle

Randomly shuffle the row order of JSON files directly in your browser. Useful for randomising data before sampling or ML train/test splits.

Top N per group

Extract the top N rows per group from JSON files directly in your browser. Get the top 5 products per category, highest scores per team, or any ranked subset — no upload required.

Unique values

Extract all distinct values from any column in JSON files directly in your browser. Download the unique values list — no upload required.

Sort

Sort JSON files by any column, ascending or descending, directly in your browser.

Split

Split JSON files into multiple smaller files by row count, directly in your browser.

Merge

Merge and concatenate multiple JSON files into one, directly in your browser.

Rename

Rename columns in JSON files instantly in your browser. No upload, no server — your data stays on your device.

Transpose

Transpose JSON files — flip rows and columns — directly in your browser. No upload, no server.

Unpivot

Reshape JSON files from wide to long format directly in your browser. Melt multiple columns into variable/value pairs — no upload required.

Flatten

Flatten nested JSON structures in JSON files into a flat table directly in your browser. Nested objects are expanded into prefixed columns — no upload required.

Split column

Split a column into multiple columns by delimiter in JSON files directly in your browser. Turn "First Last" into separate first and last name columns — no upload required.

Combine columns

Combine multiple columns into one in JSON files directly in your browser. Merge first name and last name, join address fields, or concatenate any columns with a custom separator — no upload required.

Group concatenate

Concatenate text values within each group in JSON files directly in your browser. Group rows by a column and join the values of another column into a single delimited string — no upload required.

Compare

Compare two JSON files directly in your browser. See rows only in file A, only in file B, and rows common to both — no upload required.

Compare schemas

Compare the schemas of two JSON files directly in your browser. See which columns exist in each file and spot type mismatches — no upload required.

Calculated column

Add a new column to JSON files computed from an arithmetic expression over existing columns. No formulas, no code — just point and click.

Conditional column

Add a new column to JSON files based on an if/else condition directly in your browser. Set a value for rows that match and a different value for rows that don't — no upload required.

Add row numbers

Add a row number index column to JSON files directly in your browser. Set the column name and starting number — no upload required.

Add UUID column

Add a UUID column to JSON files directly in your browser. Generate random UUIDv4 or time-ordered UUIDv7 identifiers for every row. Choose the column name and position — no upload required.

Hash columns

Anonymise or pseudonymise columns in JSON files by replacing values with MD5, SHA-256, or DuckDB hashes — directly in your browser. Useful for GDPR compliance and sharing data without exposing PII — no upload required.

Round numbers

Round numeric columns in JSON files to any number of decimal places directly in your browser. Set precision per column with a simple slider — no upload required.

Pad column

Left-pad or right-pad a column in JSON files to a fixed width directly in your browser. Zero-pad numeric codes, pad product IDs to a fixed length, or right-pad text fields — no upload required.

Bin column

Bucket a numeric column in JSON files into labelled ranges — equal-width bins or custom edges. Runs entirely in your browser.

Regex extract

Extract text matching a regular expression from JSON files directly in your browser. Pull out emails, URLs, phone numbers, or any pattern into a new column — no upload required.

Extract JSON column

Extract values from a JSON-encoded column in JSON files into a new flat column using a JSON path expression. Runs in your browser.

Parse URLs

Parse URL columns in JSON files and extract host, path, query string, and fragment into separate columns — directly in your browser, no upload required.

Parse dates

Parse and convert date columns in JSON files between formats and timezones directly in your browser. Supports ISO 8601, US/EU dates, Unix timestamps, and custom patterns — no upload required.

Format timestamps

Reformat timestamp and date columns in JSON files directly in your browser. Convert between ISO 8601, Unix epoch, US date, and custom strftime patterns — no upload required.

Date difference

Calculate the difference between two date or timestamp columns in JSON files directly in your browser. Output in days, months, years, hours, minutes, or seconds — no upload required.

Truncate dates

Truncate date and timestamp columns in JSON files to a chosen precision — year, quarter, month, week, day, hour, or minute — directly in your browser. Rounds timestamps down to the start of each period. No upload required.

Aggregate

Group and aggregate JSON files by any column directly in your browser. Calculate sum, average, min, max, and count for any numeric column — no upload required.

Count by value

Group and count rows by any column in JSON files directly in your browser. Sort by frequency or value to find the most common entries — no upload required.

Percent of total

Add a percentage-of-total column to JSON files directly in your browser. Show each row's share of the grand total, or the share within each group — no upload required.

Percentile

Compute percentiles, median, MAD, mode, and kurtosis for numeric columns in JSON files directly in your browser. Optionally group by a category column. Results download as CSV — no upload required.

Arg max / min

Find the value of one column at the row where another column is maximum or minimum in JSON files — directly in your browser. Optionally group by a category to get per-group results. No upload required.

Rank

Add a rank column to JSON files based on any column's values. Choose RANK, DENSE RANK, or ROW NUMBER, with optional partitioning — runs entirely in your browser.

Running total

Add a running total column to JSON files for any numeric column. Optionally order by a date or sequence column and restart totals per group — no upload required.

Moving average

Add a moving average, rolling sum, rolling min, or rolling max column to JSON files directly in your browser. Choose window size, order-by column, and optional partitioning — no upload required.

Lag / lead

Add a LAG or LEAD column to JSON files to shift any column forward or backward by N rows. See previous day's sales, next value in a sequence, or any time-shifted comparison — runs entirely in your browser.

Normalize

Normalize numeric columns in JSON files using min-max scaling (0–1) or z-score standardisation (mean=0, std=1). Adds new columns alongside the originals — no upload required.

Detect outliers

Detect statistical outliers in JSON files directly in your browser. Flag or remove rows where numeric values exceed a chosen number of standard deviations from the mean — no upload required.

Correlation matrix

Compute a Pearson correlation matrix for numeric columns in JSON files directly in your browser. Instantly spot which variables move together — colour-coded heatmap, no upload required.