Check Palindrome Text

A palindrome is text that reads the same forwards and backwards, like "racecar," "madam," or "A man, a plan, a canal: Panama." This tool checks palindromes by: (1) Normalizing your text—removing spaces, punctuation, and converting to lowercase ("Race-car!" becomes "racecar"), (2) Reversing the normalized text, and (3) Comparing if the forward and backward versions match exactly. If they're identical, it's a valid palindrome. The tool provides instant validation with visual feedback (green checkmark for valid, red X for invalid).

The checker uses strict alphanumeric palindrome rules: (1) Removes all non-alphanumeric characters—spaces, punctuation (.,-!?), symbols (@#$%), and special characters are ignored. (2) Converts to lowercase—"Racecar" and "racecar" are treated identically. (3) Compares character-by-character—the normalized forward text must exactly match the normalized backward text. This means "A man, a plan, a canal: Panama" becomes "amanaplanacanalpanama" which is a valid palindrome. Numbers are preserved ("12321" is valid).

Yes! Enable Batch Mode to check multiple texts simultaneously. Enter each text on a separate line and the tool will validate each one independently, showing individual results for every line. Perfect for validating lists of words, checking entire datasets, or testing multiple phrases. The statistics panel displays: total texts checked, how many are valid palindromes, how many are invalid, and the success percentage. Each result is color-coded (green for valid, red for invalid) for quick visual scanning.

Click the Upload button to load .txt or .md files containing text to validate. The tool processes files entirely in your browser—no server uploads, complete privacy. After validation, click Download Report to save a detailed analysis as a .txt file. The report includes: each input text, validation status (✓ or ✗), normalized forward and backward versions, and summary statistics. Perfect for bulk validation of word lists, testing datasets for programming projects, or archiving validation results.

Click Show Comparison to display the normalized forward and backward versions side-by-side. This visual comparison helps you: (1) Understand why text is or isn't a palindrome, (2) See exactly what characters were removed during normalization, (3) Verify the validation logic is working correctly, (4) Explain palindrome concepts to students or colleagues. In batch mode, comparison shows forward/backward for each individual item. Great for educational purposes, debugging text processing, or verifying unexpected results.

The statistics panel shows four key metrics: (1) Checked (blue): Total number of texts validated, (2) Valid (green): Number of palindromes found, (3) Invalid (red): Number of non-palindromes, and (4) Success % (purple): Percentage of valid palindromes. In single-text mode, these show 1/0 or 0/1. In batch mode, they aggregate across all lines. These metrics help you quickly assess bulk validation results, track success rates, or verify data quality in large datasets.

When you apply palindrome rules—remove spaces and punctuation, ignore case—this sentence becomes "wasitacaroracatisaw". Reading it backwards gives the exact same sequence: "wasitacaroracatisaw". The original has spaces ("Was it a car...") and punctuation ("?"), but palindromes only care about the letter sequence. This is why many famous palindromes are full sentences that become symmetrical when normalized. Other examples: "A man, a plan, a canal: Panama" → "amanaplanacanalpanama" (perfect palindrome).

Yes! Numbers are alphanumeric characters, so they're preserved during normalization. "12321" is a valid palindrome. "2002" is valid. "12345" is not. You can also check mixed alphanumeric text like "a1b2b1a" (valid) or "test123test" (invalid). This works seamlessly in batch mode too—upload a file of numbers and validate hundreds at once. Perfect for testing data sequences, validating IDs, checking symmetrical patterns in datasets, or coding challenges involving numeric palindromes.

Absolutely. All processing happens 100% in your browser using JavaScript. Your text never leaves your device, isn't sent to any server, isn't logged or stored anywhere. Even uploaded files are processed locally. You can verify this by checking your browser's Network tab—zero data transmission occurs. This is a privacy-first tool ideal for checking sensitive text (personal messages, confidential data, proprietary word lists) without any security concerns. Your palindromes are your business.

Programming: Validate algorithm outputs, test palindrome detection functions, create unit test datasets, solve coding challenges. Education: Teach symmetry concepts, demonstrate text normalization, create interactive learning exercises. Wordplay & Games: Verify puzzle solutions, validate word game submissions, check creative writing constraints. Data Validation: Ensure ID numbers follow palindromic patterns, verify symmetrical product codes, validate data integrity. Linguistics: Study palindromic phrases across languages, analyze text patterns, research linguistic symmetry. Quality Assurance: Test text processing systems, validate normalization logic, check edge cases in palindrome detectors.