How much fiber is in lentils?
Lentils has 7.8 g of fiber per 1/2 cup cooked (99 g) — about 28% of the 28 g Daily Value. That's 7.9 g of fiber per 100 g.
USDA FoodData Central · cooked, boiled · FDC 172421
Fiber by portion
| Portion | Fiber | % DV | Total carbs | Net carbs | Calories |
|---|---|---|---|---|---|
| 1/2 cup cooked (99 g) | 7.8 g | 28% | 19.9 g | 12.1 g | 115 |
| 100 g | 7.9 g | 28% | 20.1 g | 12.2 g | 116 |
| 1 oz (28 g) | 2.2 g | 8% | 5.7 g | 3.5 g | 33 |
% DV against the FDA Daily Value of 28 g of fiber. Net carbs = total carbs − fiber, since fiber isn't digested like other carbs. Values from USDA per-100 g data (FDC 172421, SR Legacy). cooked, boiled.
Lentils are one of the best fiber foods you can keep in a cupboard. A 1/2-cup serving of cooked lentils (99 g) delivers about 7.8 g of fiber — roughly 28% of the 28 g Daily Value — from a side dish that costs pennies and cooks in half an hour. Per 100 g that’s 7.9 g of fiber, and a full cup pushes past 16 g, more than half a day’s worth in one bowl. When people ask which cheap, filling staple loads up on fiber, lentils are near the top of the list.
Why lentils are such a strong fiber source
The fiber in lentils does two jobs at once, because it comes in both soluble and insoluble forms. The insoluble fiber adds bulk and keeps digestion moving; the soluble fiber forms a gel that slows things down, steadies the release of energy, and feeds the bacteria in your gut. That combination is a big part of why a 1/2-cup serving keeps you full far longer than its ~115 calories would suggest — fiber and the protein lentils carry both slow the meal down. You don’t have to think about the soluble-versus-insoluble split; eating the lentils gets you a healthy dose of each.
The net-carb payoff
That fiber also rewrites how carby lentils actually are. A 1/2 cup shows about 19.9 g of total carbs, which sounds like a lot — but fiber isn’t digested into blood sugar, so it comes off the total. Subtract the 7.8 g of fiber and the net carbs land near 12 g. That’s the whole reason a legume that looks starchy on paper eats so much lighter: a big share of its carbohydrate is fiber your body never absorbs. The same fiber slows how the rest of the carbs hit your bloodstream, which is why lentils sit well with people watching blood sugar.
Lentils aren’t only a fiber story, though — that same 1/2 cup brings roughly 9 g of plant protein for the price. For that side of the picture, see protein in lentils, and check the label’s fiber line on any packaged or canned version, since cooking and processing can shift it.
Frequently Asked Questions
How much fiber is in 1/2 cup of lentils?
About 7.8 g of fiber in a 1/2-cup serving of cooked lentils (99 g), which is 7.9 g per 100 g (USDA FDC 172421). A full cup roughly doubles that to about 16 g — most of a day's fiber from a single bowl.
What percent of the daily value for fiber is that?
Roughly 28% of the Daily Value. The FDA sets the fiber DV at 28 g, so a 1/2-cup side of lentils covers more than a quarter of it in one go — and a full cup gets you close to 60%. Few everyday foods do that per serving.
Is the fiber in lentils soluble or insoluble?
Both, with a useful share of soluble fiber. Lentils carry a mix: insoluble fiber adds bulk and keeps things moving, while their soluble fiber forms a gel that slows digestion and feeds gut bacteria. You don't need to track the split — eating lentils gets you both types at once.
How do the fiber and net carbs in lentils relate?
The fiber is what makes lentils' net carbs low. A 1/2 cup has about 19.9 g total carbs, but subtract the 7.8 g of fiber and the net carbs land near 12 g. Fiber isn't digested into blood sugar, so it comes off the total — which is why a legume that looks carby eats much lighter.
How much fiber is in a whole cup of cooked lentils?
About 16 g per cooked cup (198 g) — roughly 57% of the 28 g Daily Value. That's a main-dish portion, and at that size lentils alone supply more than half a day's fiber alongside ~18 g of protein.
When was this data last verified?
2026-06-04, against USDA FoodData Central FDC 172421 (Lentils, mature seeds, cooked, boiled, without salt; SR Legacy). We re-verify reference pages periodically and update when USDA revises the entry.
Whole-food values are USDA reference data, not a Labelgrade (that score is for branded packaged products). See our methodology and the carbs & net carbs lane.