El límite de datos es bajo.

Because límite is a masculine noun in Spanish, even though it does not end in -o.

So:

• el límite = the limit
• un límite = a limit

This is something learners often just have to memorize, because grammatical gender in Spanish does not always match the ending of the word.

The accent mark shows where the stress goes: LÍ-mi-te.

Without the accent, Spanish pronunciation rules would make it sound different. The written accent tells you that the stress is on the first syllable.

So:

• límite = noun, limit
• limite could appear as a verb form, from limitar (for example, que él limite = that he limit)

The accent helps distinguish the noun clearly.

De datos literally means of data.

So:

• el límite de datos = the data limit

This is a very common Spanish structure:

• el vaso de agua = the glass of water
• la tarjeta de crédito = the credit card
• el plan de datos = the data plan

In this sentence, datos usually refers to mobile data or internet data.

In Spanish, datos is normally used in the plural when talking about data in the technological sense.

So Spanish commonly says:

• datos móviles = mobile data
• consumo de datos = data usage
• límite de datos = data limit

Even though English often uses data like a mass noun, Spanish usually uses datos in the plural in this context.

Because bajo here describes a quality or characteristic of the limit, not a temporary location or condition.

So:

• es bajo = it is low
• está would sound wrong here

A helpful way to think about it:

• ser is used for what something is
• estar is used for where something is or for certain states/conditions

A data limit is being described by its level, so Spanish uses ser:

• El límite de datos es bajo.

In Spanish, adjectives often come after the noun, especially when they describe an objective quality.

So:

• el límite es bajo = the limit is low
• un precio bajo = a low price
• una temperatura baja = a low temperature

That is the normal position here. Putting bajo before the noun would sound unusual in this context.

Because bajo agrees with límite, and límite is masculine singular.

Agreement rules:

• masculine singular: bajo
• feminine singular: baja
• masculine plural: bajos
• feminine plural: bajas

Examples:

• El límite es bajo.
• La velocidad es baja.

Even though datos is plural, the adjective is describing límite, not datos.

Yes. Here bajo means low in the sense of small in amount/level.

It is a very natural adjective with things like:

• precio bajo = low price
• salario bajo = low salary
• nivel bajo = low level
• límite bajo = low limit

So El límite de datos es bajo is a natural way to say that the allowed amount of data is not much.

Normally, no. In standard Spanish, es bajo is the natural choice.

Está bajo might occasionally appear in other contexts when something has become low or is currently at a low level, but with límite, Spanish normally treats it as a defining characteristic and says es bajo.

So for learners, the safest and most natural version is:

• El límite de datos es bajo.

Usually, yes. In everyday Spanish, datos in this kind of sentence most often refers to mobile data or an internet data allowance.

Depending on context, it could mean:

• a phone plan’s data cap
• an internet package limit
• a general data allowance

If someone says this in normal conversation, many people will assume they mean mobile data unless the context suggests something else.

No, not in normal Spanish.

Spanish usually needs the definite article here:

• El límite de datos es bajo.

Leaving out el would sound incomplete or unnatural.

But you could change the determiner:

• Mi límite de datos es bajo. = My data limit is low.
• Tu límite de datos es bajo. = Your data limit is low.
• Este límite de datos es bajo. = This data limit is low.

Yes, depending on what you want to emphasize.

Some natural alternatives are:

• Tengo pocos datos. = I have little data / I don’t have much data left.
• El plan de datos es limitado. = The data plan is limited.
• Hay muy pocos datos disponibles. = There is very little data available.

But if you specifically want to talk about the limit/cap itself, then El límite de datos es bajo is a good sentence.