Tbsp to Tsp Converter Calculator

Tablespoons (tbsp)

Supports decimals and mixed fractions.

Measure standard US kitchen Metric kitchen

Both use 1 tbsp = 3 tsp.

Batch multiplier

Scale for multiple pots or batches.

Decimal precision 0 decimals 1 decimals 2 decimals 3 decimals 4 decimals 5 decimals 6 decimals

Rounding mode Round (nearest) Round up (safer for weak mixes) Round down (safer for strong mixes)

Include mL output

Show milliliters (mL)

Helpful for syringes and measuring cups.

Notes (optional)

Convert Clear history Reset form

Example Data Table

Values assume 1 tbsp equals 3 tsp. Choose your standard for accurate mL output.

Formula Used

• Teaspoons = Tablespoons × 3
• Scaled tablespoons = Tablespoons × Multiplier
• Milliliters = Teaspoons × mL-per-tsp (US: 4.92892159375, Metric: 5)
• Rounding applies after conversion using your chosen mode.

How to Use This Calculator

1. Enter the tablespoons from your garden label or recipe.
2. Pick US or metric to match your measuring spoons.
3. Add a multiplier to scale for more pots or batches.
4. Choose precision and rounding that fit your dosing style.
5. Press Convert and read the result above the form.
6. Download CSV or PDF to keep a clean mixing log.

Why spoon accuracy matters in garden feeding

Most water‑soluble fertilizers, compost tea concentrates, and micronutrient powders are dosed by volume, not weight. A small error in spoon size can shift nitrogen, potassium, or iron levels enough to burn seedlings or stall growth. Converting tablespoons to teaspoons gives finer control when labels specify small doses, or when you split a recipe for smaller watering cans.

When tablespoons become the wrong tool

Tablespoons are convenient for large batches, but they are coarse for foliar sprays, seedling trays, and hydroponic top‑offs. Teaspoons help you target light feeding schedules, reduce runoff, and keep electrical conductivity steadier. If you are mixing multiple products, teaspoons also make it easier to add increments without overshooting the final concentration.

Standards, milliliters, and repeatable mixes

This calculator keeps the core ratio simple: 1 tablespoon equals 3 teaspoons. Where standards matter is milliliters. US teaspoons are about 4.9289 mL, while metric teaspoons are 5 mL. Selecting the correct standard helps when you use syringes, measuring cups, or automatic dosers that read in mL.

Scaling with multipliers for batches and zones

The multiplier lets you scale a label dose for several pots, a drip irrigation zone, or repeated refills. For example, if one pot needs 2 tbsp per gallon, four identical pots need a 4× batch. The calculator first scales tablespoons, then converts to teaspoons, then applies your rounding choice for practical measuring.

Logging results for consistency and compliance

Keeping a mixing log reduces variability between helpers and seasons. Exporting CSV supports audits for community gardens and small nurseries, and it also helps you spot patterns, like which feed rates caused leaf tip burn or algae blooms. PDF snapshots are useful for printouts near the potting bench. Use the notes field to record product names, dilution targets, and weather conditions. Over time, these records improve training, reduce waste, and protect beneficial microbes. When changing brands, recalc doses rather than guessing, because scoop volumes and granule density vary from bag to bag.

FAQs

1) Is the conversion always 1 tbsp = 3 tsp?

Yes for standard culinary measuring spoons. This calculator uses 3 teaspoons per tablespoon, then applies your multiplier and rounding. Only the milliliter value changes with US versus metric teaspoons.

2) Why does the mL result differ between standards?

A teaspoon is a volume unit, and the exact milliliters depend on the standard. Metric teaspoons are 5 mL, while US teaspoons are about 4.9289 mL. Pick the one that matches your tools.

3) Can I enter fractions like 1 1/2?

Yes. The input accepts whole numbers, decimals, simple fractions, and mixed fractions such as 1 1/2. This helps when garden labels use fractional spoon measures.

4) Which rounding mode should I use for fertilizers?

For strong feeds and sensitive plants, rounding down is safer. For mild blends, rounding to nearest is fine. Rounding up can help when a product label expects a minimum dose, but stay within label limits.

5) What does the batch multiplier do?

It scales your tablespoons before conversion. Use it when mixing for multiple containers, larger watering cans, or repeat refills. A 3× multiplier means you are preparing three identical doses at once.

6) How is history stored, and is it permanent?

History is saved in your current browser session on the server side and capped at 50 rows. Clearing history or ending the session removes it. Export CSV or PDF if you need long‑term records.