NDJSON Tools

Deduplicate NDJSON Files Online

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

Filter NDJSON Files Online

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

Sort NDJSON Files Online

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

Split NDJSON Files Online

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

Sample NDJSON Files Online

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

Manage Columns in NDJSON Files Online

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

Rename Columns in NDJSON Files Online

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

Merge NDJSON Files Online

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

Trim Whitespace in NDJSON Files Online

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

Fill Empty Values in NDJSON Files Online

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

Transpose NDJSON Files Online

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

Extract Head of NDJSON Files Online

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

Extract Tail of NDJSON Files Online

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

Add Row Numbers to NDJSON Files Online

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

Validate NDJSON Files Online

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

Flatten NDJSON Files Online

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

Count Values in NDJSON Files Online

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

Extract Unique Values from NDJSON Files Online

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

Compare NDJSON Files Online

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

Format Timestamps in NDJSON Files Online

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

Find & Replace in NDJSON Files Online

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

Split Column in NDJSON Files Online

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

Combine Columns in NDJSON Files Online

Combine multiple columns into one in NDJSON 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.

Convert Case in NDJSON Files Online

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

Aggregate NDJSON Files Online

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

Round Numbers in NDJSON Files Online

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

Add Conditional Column to NDJSON Files Online

Add a new column to NDJSON 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.

Extract with Regex from NDJSON Files Online

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

Parse Dates in NDJSON Files Online

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

Compare Schema of NDJSON Files Online

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

Cast Column Types in NDJSON Files Online

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

Unpivot NDJSON Files Online

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

Convert Encoding of NDJSON Files Online

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

Shuffle NDJSON Files Online

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

Bin Column in NDJSON Files Online

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

Add Calculated Column to NDJSON Files Online

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

Extract JSON Column from NDJSON Files Online

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

Calculate Date Difference in NDJSON Files Online

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

Normalize Columns in NDJSON Files Online

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

Rank Rows in NDJSON Files Online

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

Add Cumulative Sum to NDJSON Files Online

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

Detect Outliers in NDJSON Files Online

Detect statistical outliers in NDJSON 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.

Validate Email Addresses in NDJSON Files Online

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

Add Moving Average to NDJSON Files Online

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

Search Text in NDJSON Files Online

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

Get Top N Rows from NDJSON Files Online

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

Add Percent of Total to NDJSON Files Online

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

Parse URL Column in NDJSON Files Online

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

Add Lag / Lead Column to NDJSON Files Online

Add a LAG or LEAD column to NDJSON 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.

Filter by Date Range NDJSON Files Online

Filter NDJSON 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.

Compute Correlation Matrix for NDJSON Files Online

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

Find Fuzzy Duplicates in NDJSON Files Online

Find near-duplicate rows in NDJSON 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.

Hash & Anonymise Columns in NDJSON Files Online

Anonymise or pseudonymise columns in NDJSON 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.

Group Concatenate NDJSON Files Online

Concatenate text values within each group in NDJSON 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.

Truncate Dates in NDJSON Files Online

Truncate date and timestamp columns in NDJSON 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.

Coalesce Columns in NDJSON Files Online

Fill null values in NDJSON 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.

Add UUID Column to NDJSON Files Online

Add a UUID column to NDJSON 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.

Pad Column in NDJSON Files Online

Left-pad or right-pad a column in NDJSON 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.

Compute Percentiles for NDJSON Files Online

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

Find Arg Max / Min in NDJSON Files Online

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

NDJSON Viewer Online

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