How do I decode a Base64 string online?

Paste your Base64 string into SmartDevBox at smartdevbox.com. It automatically detects Base64 encoding and decodes it instantly — no configuration needed.

How do I decode a JWT token without a secret?

Paste your JWT token into SmartDevBox. The JWT Inspector tool decodes the header and payload and displays them as readable JSON. Note: this decodes but does not verify the signature — you don't need the secret to read the claims.

How do I format or pretty-print JSON?

Paste your minified or unformatted JSON into SmartDevBox. The JSON Formatter tool detects it automatically and pretty-prints it with configurable indentation.

How do I convert a Unix timestamp to a human-readable date?

Paste a Unix timestamp (e.g. 1700000000) into SmartDevBox. The Unix Timestamp converter detects it and shows the equivalent date and time in UTC and your local timezone.

How do I compute a SHA-256 hash online?

Use the Hash Generator tool on SmartDevBox. Paste any text and it computes MD5, SHA-1, SHA-256, and SHA-512 hashes simultaneously in the browser.

How do I parse and understand a cron expression?

Paste your cron expression (e.g. "0 9 * * 1-5") into SmartDevBox. The Cron Job Parser explains it in plain English and shows the next scheduled run times.

How do I decode an X.509 certificate online?

Paste a PEM-encoded certificate (beginning with -----BEGIN CERTIFICATE-----) into SmartDevBox. The Certificate Decoder extracts and displays the subject, issuer, validity dates, public key, and extensions.

Is SmartDevBox free to use?

Yes. SmartDevBox is completely free with no account or sign-up required. All tools run in the browser. An optional AI mode (for ambiguous input detection) can be enabled with your own OpenAI API key.

Does SmartDevBox send my data to a server?

No. All tools run entirely in the browser using client-side JavaScript. Your data never leaves your machine unless you opt into the AI mode, which sends input to OpenAI for format detection.

JSON to CSV Converter — Convert JSON Arrays to CSV Online

JSON to CSV Converter flattens a JSON array of objects into comma-separated values with column headers derived from the JSON keys. Nested objects are serialized as JSON strings within the CSV cell.

Common Use Cases

Exporting API response data to Excel or Google Sheets
Converting database query results from JSON to CSV
Preparing data for CSV-based reporting tools

Frequently Asked Questions

How do I convert JSON to CSV?

Paste a JSON array of objects into SmartDevBox and select the JSON → CSV tool. It produces comma-separated output with column headers derived from the JSON keys.

What happens to nested objects in the JSON?

Nested objects and arrays are serialized as JSON strings within the CSV cell. Flat primitives (strings, numbers, booleans) are written as plain values.

Privacy & Security

This tool runs entirely in your browser using client-side JavaScript. No data is sent to a server — your input never leaves your machine. SmartDevBox has no account system, no usage tracking, and no paid tier. See the Privacy & Security page for full details.

JSON to TSV ConverterConvert JSON arrays to TSV (tab-separated values) format instantly. Free, no sign-up, 100% client-side.
CSV to JSON ConverterConvert CSV data to a JSON array of objects instantly. Headers become keys. Free, no sign-up, 100% client-side.
JSON FormatterFormat and pretty-print JSON instantly in your browser. Validates syntax and shows error location. Free, no sign-up, 100% client-side.
JSON to YAML ConverterConvert JSON to YAML format instantly in your browser. Free, no sign-up, 100% client-side.