Query String Builder

The Query String Builder lets you compose valid query strings from a set of key–value pairs. It appends keys in order and handles repeated keys, producing a copy‑ready ?a=1&b=2 string.

Use it when crafting links for campaigns, debugging API calls, or generating test URLs. Everything runs in your browser for instant feedback.

Key features

• Add unlimited rows for parameters
• Preserves repeated keys for multi‑value params
• Copy the result with one click
• Local persistence of your last set of rows

Common use cases

• Composing UTM tags for marketing links
• Assembling query parameters for API requests
• Testing route handling with controlled inputs

Privacy & security: all data stays in your browser; nothing is uploaded.

1. Click “Add Row” to insert key–value pairs.
2. Type a key and value in each row.
3. Click “Sample” to load a common UTM set.
4. Review the generated string below.
5. Click “Copy Output” to copy the ?query string.
6. Use “Clear” to reset to an empty template.

Tips

• Leave the key empty to omit a row.
• Repeat keys for multi‑value parameters like tag.
• Use the encoder to percent‑encode special characters.

Troubleshooting

• Empty output → All keys are blank; fill at least one key.
• Unexpected characters → Percent‑encode values if the target system requires it.
• Order sensitive → Add rows in the desired order; the tool appends in sequence.